| /* Standard problems for dataflow support routines. |
| Copyright (C) 1999-2017 Free Software Foundation, Inc. |
| Originally contributed by Michael P. Hayes |
| (m.hayes@elec.canterbury.ac.nz, mhayes@redhat.com) |
| Major rewrite contributed by Danny Berlin (dberlin@dberlin.org) |
| and Kenneth Zadeck (zadeck@naturalbridge.com). |
| |
| This file is part of GCC. |
| |
| GCC is free software; you can redistribute it and/or modify it under |
| the terms of the GNU General Public License as published by the Free |
| Software Foundation; either version 3, or (at your option) any later |
| version. |
| |
| GCC is distributed in the hope that it will be useful, but WITHOUT ANY |
| WARRANTY; without even the implied warranty of MERCHANTABILITY or |
| FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License |
| for more details. |
| |
| You should have received a copy of the GNU General Public License |
| along with GCC; see the file COPYING3. If not see |
| <http://www.gnu.org/licenses/>. */ |
| |
| #include "config.h" |
| #include "system.h" |
| #include "coretypes.h" |
| #include "backend.h" |
| #include "target.h" |
| #include "rtl.h" |
| #include "df.h" |
| #include "memmodel.h" |
| #include "tm_p.h" |
| #include "insn-config.h" |
| #include "cfganal.h" |
| #include "dce.h" |
| #include "valtrack.h" |
| #include "dumpfile.h" |
| #include "rtl-iter.h" |
| |
| /* Note that turning REG_DEAD_DEBUGGING on will cause |
| gcc.c-torture/unsorted/dump-noaddr.c to fail because it prints |
| addresses in the dumps. */ |
| #define REG_DEAD_DEBUGGING 0 |
| |
| #define DF_SPARSE_THRESHOLD 32 |
| |
| static bitmap_head seen_in_block; |
| static bitmap_head seen_in_insn; |
| |
| /*---------------------------------------------------------------------------- |
| Utility functions. |
| ----------------------------------------------------------------------------*/ |
| |
| /* Generic versions to get the void* version of the block info. Only |
| used inside the problem instance vectors. */ |
| |
| /* Dump a def-use or use-def chain for REF to FILE. */ |
| |
| void |
| df_chain_dump (struct df_link *link, FILE *file) |
| { |
| fprintf (file, "{ "); |
| for (; link; link = link->next) |
| { |
| fprintf (file, "%c%d(bb %d insn %d) ", |
| DF_REF_REG_DEF_P (link->ref) |
| ? 'd' |
| : (DF_REF_FLAGS (link->ref) & DF_REF_IN_NOTE) ? 'e' : 'u', |
| DF_REF_ID (link->ref), |
| DF_REF_BBNO (link->ref), |
| DF_REF_IS_ARTIFICIAL (link->ref) |
| ? -1 : DF_REF_INSN_UID (link->ref)); |
| } |
| fprintf (file, "}"); |
| } |
| |
| |
| /* Print some basic block info as part of df_dump. */ |
| |
| void |
| df_print_bb_index (basic_block bb, FILE *file) |
| { |
| edge e; |
| edge_iterator ei; |
| |
| fprintf (file, "\n( "); |
| FOR_EACH_EDGE (e, ei, bb->preds) |
| { |
| basic_block pred = e->src; |
| fprintf (file, "%d%s ", pred->index, e->flags & EDGE_EH ? "(EH)" : ""); |
| } |
| fprintf (file, ")->[%d]->( ", bb->index); |
| FOR_EACH_EDGE (e, ei, bb->succs) |
| { |
| basic_block succ = e->dest; |
| fprintf (file, "%d%s ", succ->index, e->flags & EDGE_EH ? "(EH)" : ""); |
| } |
| fprintf (file, ")\n"); |
| } |
| |
| |
| /*---------------------------------------------------------------------------- |
| REACHING DEFINITIONS |
| |
| Find the locations in the function where each definition site for a |
| pseudo reaches. In and out bitvectors are built for each basic |
| block. The id field in the ref is used to index into these sets. |
| See df.h for details. |
| |
| If the DF_RD_PRUNE_DEAD_DEFS changeable flag is set, only DEFs reaching |
| existing uses are included in the global reaching DEFs set, or in other |
| words only DEFs that are still live. This is a kind of pruned version |
| of the traditional reaching definitions problem that is much less |
| complex to compute and produces enough information to compute UD-chains. |
| In this context, live must be interpreted in the DF_LR sense: Uses that |
| are upward exposed but maybe not initialized on all paths through the |
| CFG. For a USE that is not reached by a DEF on all paths, we still want |
| to make those DEFs that do reach the USE visible, and pruning based on |
| DF_LIVE would make that impossible. |
| ----------------------------------------------------------------------------*/ |
| |
| /* This problem plays a large number of games for the sake of |
| efficiency. |
| |
| 1) The order of the bits in the bitvectors. After the scanning |
| phase, all of the defs are sorted. All of the defs for the reg 0 |
| are first, followed by all defs for reg 1 and so on. |
| |
| 2) There are two kill sets, one if the number of defs is less or |
| equal to DF_SPARSE_THRESHOLD and another if the number of defs is |
| greater. |
| |
| <= : Data is built directly in the kill set. |
| |
| > : One level of indirection is used to keep from generating long |
| strings of 1 bits in the kill sets. Bitvectors that are indexed |
| by the regnum are used to represent that there is a killing def |
| for the register. The confluence and transfer functions use |
| these along with the bitmap_clear_range call to remove ranges of |
| bits without actually generating a knockout vector. |
| |
| The kill and sparse_kill and the dense_invalidated_by_call and |
| sparse_invalidated_by_call both play this game. */ |
| |
| /* Private data used to compute the solution for this problem. These |
| data structures are not accessible outside of this module. */ |
| struct df_rd_problem_data |
| { |
| /* The set of defs to regs invalidated by call. */ |
| bitmap_head sparse_invalidated_by_call; |
| /* The set of defs to regs invalidate by call for rd. */ |
| bitmap_head dense_invalidated_by_call; |
| /* An obstack for the bitmaps we need for this problem. */ |
| bitmap_obstack rd_bitmaps; |
| }; |
| |
| |
| /* Free basic block info. */ |
| |
| static void |
| df_rd_free_bb_info (basic_block bb ATTRIBUTE_UNUSED, |
| void *vbb_info) |
| { |
| struct df_rd_bb_info *bb_info = (struct df_rd_bb_info *) vbb_info; |
| if (bb_info) |
| { |
| bitmap_clear (&bb_info->kill); |
| bitmap_clear (&bb_info->sparse_kill); |
| bitmap_clear (&bb_info->gen); |
| bitmap_clear (&bb_info->in); |
| bitmap_clear (&bb_info->out); |
| } |
| } |
| |
| |
| /* Allocate or reset bitmaps for DF_RD blocks. The solution bits are |
| not touched unless the block is new. */ |
| |
| static void |
| df_rd_alloc (bitmap all_blocks) |
| { |
| unsigned int bb_index; |
| bitmap_iterator bi; |
| struct df_rd_problem_data *problem_data; |
| |
| if (df_rd->problem_data) |
| { |
| problem_data = (struct df_rd_problem_data *) df_rd->problem_data; |
| bitmap_clear (&problem_data->sparse_invalidated_by_call); |
| bitmap_clear (&problem_data->dense_invalidated_by_call); |
| } |
| else |
| { |
| problem_data = XNEW (struct df_rd_problem_data); |
| df_rd->problem_data = problem_data; |
| |
| bitmap_obstack_initialize (&problem_data->rd_bitmaps); |
| bitmap_initialize (&problem_data->sparse_invalidated_by_call, |
| &problem_data->rd_bitmaps); |
| bitmap_initialize (&problem_data->dense_invalidated_by_call, |
| &problem_data->rd_bitmaps); |
| } |
| |
| df_grow_bb_info (df_rd); |
| |
| /* Because of the clustering of all use sites for the same pseudo, |
| we have to process all of the blocks before doing the analysis. */ |
| |
| EXECUTE_IF_SET_IN_BITMAP (all_blocks, 0, bb_index, bi) |
| { |
| struct df_rd_bb_info *bb_info = df_rd_get_bb_info (bb_index); |
| |
| /* When bitmaps are already initialized, just clear them. */ |
| if (bb_info->kill.obstack) |
| { |
| bitmap_clear (&bb_info->kill); |
| bitmap_clear (&bb_info->sparse_kill); |
| bitmap_clear (&bb_info->gen); |
| } |
| else |
| { |
| bitmap_initialize (&bb_info->kill, &problem_data->rd_bitmaps); |
| bitmap_initialize (&bb_info->sparse_kill, &problem_data->rd_bitmaps); |
| bitmap_initialize (&bb_info->gen, &problem_data->rd_bitmaps); |
| bitmap_initialize (&bb_info->in, &problem_data->rd_bitmaps); |
| bitmap_initialize (&bb_info->out, &problem_data->rd_bitmaps); |
| } |
| } |
| df_rd->optional_p = true; |
| } |
| |
| |
| /* Add the effect of the top artificial defs of BB to the reaching definitions |
| bitmap LOCAL_RD. */ |
| |
| void |
| df_rd_simulate_artificial_defs_at_top (basic_block bb, bitmap local_rd) |
| { |
| int bb_index = bb->index; |
| df_ref def; |
| FOR_EACH_ARTIFICIAL_DEF (def, bb_index) |
| if (DF_REF_FLAGS (def) & DF_REF_AT_TOP) |
| { |
| unsigned int dregno = DF_REF_REGNO (def); |
| if (!(DF_REF_FLAGS (def) & (DF_REF_PARTIAL | DF_REF_CONDITIONAL))) |
| bitmap_clear_range (local_rd, |
| DF_DEFS_BEGIN (dregno), |
| DF_DEFS_COUNT (dregno)); |
| bitmap_set_bit (local_rd, DF_REF_ID (def)); |
| } |
| } |
| |
| /* Add the effect of the defs of INSN to the reaching definitions bitmap |
| LOCAL_RD. */ |
| |
| void |
| df_rd_simulate_one_insn (basic_block bb ATTRIBUTE_UNUSED, rtx_insn *insn, |
| bitmap local_rd) |
| { |
| df_ref def; |
| |
| FOR_EACH_INSN_DEF (def, insn) |
| { |
| unsigned int dregno = DF_REF_REGNO (def); |
| if ((!(df->changeable_flags & DF_NO_HARD_REGS)) |
| || (dregno >= FIRST_PSEUDO_REGISTER)) |
| { |
| if (!(DF_REF_FLAGS (def) & (DF_REF_PARTIAL | DF_REF_CONDITIONAL))) |
| bitmap_clear_range (local_rd, |
| DF_DEFS_BEGIN (dregno), |
| DF_DEFS_COUNT (dregno)); |
| if (!(DF_REF_FLAGS (def) |
| & (DF_REF_MUST_CLOBBER | DF_REF_MAY_CLOBBER))) |
| bitmap_set_bit (local_rd, DF_REF_ID (def)); |
| } |
| } |
| } |
| |
| /* Process a list of DEFs for df_rd_bb_local_compute. This is a bit |
| more complicated than just simulating, because we must produce the |
| gen and kill sets and hence deal with the two possible representations |
| of kill sets. */ |
| |
| static void |
| df_rd_bb_local_compute_process_def (struct df_rd_bb_info *bb_info, |
| df_ref def, |
| int top_flag) |
| { |
| for (; def; def = DF_REF_NEXT_LOC (def)) |
| { |
| if (top_flag == (DF_REF_FLAGS (def) & DF_REF_AT_TOP)) |
| { |
| unsigned int regno = DF_REF_REGNO (def); |
| unsigned int begin = DF_DEFS_BEGIN (regno); |
| unsigned int n_defs = DF_DEFS_COUNT (regno); |
| |
| if ((!(df->changeable_flags & DF_NO_HARD_REGS)) |
| || (regno >= FIRST_PSEUDO_REGISTER)) |
| { |
| /* Only the last def(s) for a regno in the block has any |
| effect. */ |
| if (!bitmap_bit_p (&seen_in_block, regno)) |
| { |
| /* The first def for regno in insn gets to knock out the |
| defs from other instructions. */ |
| if ((!bitmap_bit_p (&seen_in_insn, regno)) |
| /* If the def is to only part of the reg, it does |
| not kill the other defs that reach here. */ |
| && (!(DF_REF_FLAGS (def) & |
| (DF_REF_PARTIAL | DF_REF_CONDITIONAL | DF_REF_MAY_CLOBBER)))) |
| { |
| if (n_defs > DF_SPARSE_THRESHOLD) |
| { |
| bitmap_set_bit (&bb_info->sparse_kill, regno); |
| bitmap_clear_range (&bb_info->gen, begin, n_defs); |
| } |
| else |
| { |
| bitmap_set_range (&bb_info->kill, begin, n_defs); |
| bitmap_clear_range (&bb_info->gen, begin, n_defs); |
| } |
| } |
| |
| bitmap_set_bit (&seen_in_insn, regno); |
| /* All defs for regno in the instruction may be put into |
| the gen set. */ |
| if (!(DF_REF_FLAGS (def) |
| & (DF_REF_MUST_CLOBBER | DF_REF_MAY_CLOBBER))) |
| bitmap_set_bit (&bb_info->gen, DF_REF_ID (def)); |
| } |
| } |
| } |
| } |
| } |
| |
| /* Compute local reaching def info for basic block BB. */ |
| |
| static void |
| df_rd_bb_local_compute (unsigned int bb_index) |
| { |
| basic_block bb = BASIC_BLOCK_FOR_FN (cfun, bb_index); |
| struct df_rd_bb_info *bb_info = df_rd_get_bb_info (bb_index); |
| rtx_insn *insn; |
| |
| bitmap_clear (&seen_in_block); |
| bitmap_clear (&seen_in_insn); |
| |
| /* Artificials are only hard regs. */ |
| if (!(df->changeable_flags & DF_NO_HARD_REGS)) |
| df_rd_bb_local_compute_process_def (bb_info, |
| df_get_artificial_defs (bb_index), |
| 0); |
| |
| FOR_BB_INSNS_REVERSE (bb, insn) |
| { |
| unsigned int uid = INSN_UID (insn); |
| |
| if (!INSN_P (insn)) |
| continue; |
| |
| df_rd_bb_local_compute_process_def (bb_info, |
| DF_INSN_UID_DEFS (uid), 0); |
| |
| /* This complex dance with the two bitmaps is required because |
| instructions can assign twice to the same pseudo. This |
| generally happens with calls that will have one def for the |
| result and another def for the clobber. If only one vector |
| is used and the clobber goes first, the result will be |
| lost. */ |
| bitmap_ior_into (&seen_in_block, &seen_in_insn); |
| bitmap_clear (&seen_in_insn); |
| } |
| |
| /* Process the artificial defs at the top of the block last since we |
| are going backwards through the block and these are logically at |
| the start. */ |
| if (!(df->changeable_flags & DF_NO_HARD_REGS)) |
| df_rd_bb_local_compute_process_def (bb_info, |
| df_get_artificial_defs (bb_index), |
| DF_REF_AT_TOP); |
| } |
| |
| |
| /* Compute local reaching def info for each basic block within BLOCKS. */ |
| |
| static void |
| df_rd_local_compute (bitmap all_blocks) |
| { |
| unsigned int bb_index; |
| bitmap_iterator bi; |
| unsigned int regno; |
| struct df_rd_problem_data *problem_data |
| = (struct df_rd_problem_data *) df_rd->problem_data; |
| bitmap sparse_invalidated = &problem_data->sparse_invalidated_by_call; |
| bitmap dense_invalidated = &problem_data->dense_invalidated_by_call; |
| |
| bitmap_initialize (&seen_in_block, &df_bitmap_obstack); |
| bitmap_initialize (&seen_in_insn, &df_bitmap_obstack); |
| |
| df_maybe_reorganize_def_refs (DF_REF_ORDER_BY_REG); |
| |
| EXECUTE_IF_SET_IN_BITMAP (all_blocks, 0, bb_index, bi) |
| { |
| df_rd_bb_local_compute (bb_index); |
| } |
| |
| /* Set up the knockout bit vectors to be applied across EH_EDGES. */ |
| EXECUTE_IF_SET_IN_BITMAP (regs_invalidated_by_call_regset, 0, regno, bi) |
| { |
| if (! HARD_REGISTER_NUM_P (regno) |
| || !(df->changeable_flags & DF_NO_HARD_REGS)) |
| { |
| if (DF_DEFS_COUNT (regno) > DF_SPARSE_THRESHOLD) |
| bitmap_set_bit (sparse_invalidated, regno); |
| else |
| bitmap_set_range (dense_invalidated, |
| DF_DEFS_BEGIN (regno), |
| DF_DEFS_COUNT (regno)); |
| } |
| } |
| |
| bitmap_clear (&seen_in_block); |
| bitmap_clear (&seen_in_insn); |
| } |
| |
| |
| /* Initialize the solution bit vectors for problem. */ |
| |
| static void |
| df_rd_init_solution (bitmap all_blocks) |
| { |
| unsigned int bb_index; |
| bitmap_iterator bi; |
| |
| EXECUTE_IF_SET_IN_BITMAP (all_blocks, 0, bb_index, bi) |
| { |
| struct df_rd_bb_info *bb_info = df_rd_get_bb_info (bb_index); |
| |
| bitmap_copy (&bb_info->out, &bb_info->gen); |
| bitmap_clear (&bb_info->in); |
| } |
| } |
| |
| /* In of target gets or of out of source. */ |
| |
| static bool |
| df_rd_confluence_n (edge e) |
| { |
| bitmap op1 = &df_rd_get_bb_info (e->dest->index)->in; |
| bitmap op2 = &df_rd_get_bb_info (e->src->index)->out; |
| bool changed = false; |
| |
| if (e->flags & EDGE_FAKE) |
| return false; |
| |
| if (e->flags & EDGE_EH) |
| { |
| struct df_rd_problem_data *problem_data |
| = (struct df_rd_problem_data *) df_rd->problem_data; |
| bitmap sparse_invalidated = &problem_data->sparse_invalidated_by_call; |
| bitmap dense_invalidated = &problem_data->dense_invalidated_by_call; |
| bitmap_iterator bi; |
| unsigned int regno; |
| bitmap_head tmp; |
| |
| bitmap_initialize (&tmp, &df_bitmap_obstack); |
| bitmap_and_compl (&tmp, op2, dense_invalidated); |
| |
| EXECUTE_IF_SET_IN_BITMAP (sparse_invalidated, 0, regno, bi) |
| { |
| bitmap_clear_range (&tmp, |
| DF_DEFS_BEGIN (regno), |
| DF_DEFS_COUNT (regno)); |
| } |
| changed |= bitmap_ior_into (op1, &tmp); |
| bitmap_clear (&tmp); |
| return changed; |
| } |
| else |
| return bitmap_ior_into (op1, op2); |
| } |
| |
| |
| /* Transfer function. */ |
| |
| static bool |
| df_rd_transfer_function (int bb_index) |
| { |
| struct df_rd_bb_info *bb_info = df_rd_get_bb_info (bb_index); |
| unsigned int regno; |
| bitmap_iterator bi; |
| bitmap in = &bb_info->in; |
| bitmap out = &bb_info->out; |
| bitmap gen = &bb_info->gen; |
| bitmap kill = &bb_info->kill; |
| bitmap sparse_kill = &bb_info->sparse_kill; |
| bool changed = false; |
| |
| if (bitmap_empty_p (sparse_kill)) |
| changed = bitmap_ior_and_compl (out, gen, in, kill); |
| else |
| { |
| struct df_rd_problem_data *problem_data; |
| bitmap_head tmp; |
| |
| /* Note that TMP is _not_ a temporary bitmap if we end up replacing |
| OUT with TMP. Therefore, allocate TMP in the RD bitmaps obstack. */ |
| problem_data = (struct df_rd_problem_data *) df_rd->problem_data; |
| bitmap_initialize (&tmp, &problem_data->rd_bitmaps); |
| |
| bitmap_and_compl (&tmp, in, kill); |
| EXECUTE_IF_SET_IN_BITMAP (sparse_kill, 0, regno, bi) |
| { |
| bitmap_clear_range (&tmp, |
| DF_DEFS_BEGIN (regno), |
| DF_DEFS_COUNT (regno)); |
| } |
| bitmap_ior_into (&tmp, gen); |
| changed = !bitmap_equal_p (&tmp, out); |
| if (changed) |
| bitmap_move (out, &tmp); |
| else |
| bitmap_clear (&tmp); |
| } |
| |
| if (df->changeable_flags & DF_RD_PRUNE_DEAD_DEFS) |
| { |
| /* Create a mask of DEFs for all registers live at the end of this |
| basic block, and mask out DEFs of registers that are not live. |
| Computing the mask looks costly, but the benefit of the pruning |
| outweighs the cost. */ |
| struct df_rd_bb_info *bb_info = df_rd_get_bb_info (bb_index); |
| bitmap regs_live_out = &df_lr_get_bb_info (bb_index)->out; |
| bitmap live_defs = BITMAP_ALLOC (&df_bitmap_obstack); |
| unsigned int regno; |
| bitmap_iterator bi; |
| |
| EXECUTE_IF_SET_IN_BITMAP (regs_live_out, 0, regno, bi) |
| bitmap_set_range (live_defs, |
| DF_DEFS_BEGIN (regno), |
| DF_DEFS_COUNT (regno)); |
| changed |= bitmap_and_into (&bb_info->out, live_defs); |
| BITMAP_FREE (live_defs); |
| } |
| |
| return changed; |
| } |
| |
| /* Free all storage associated with the problem. */ |
| |
| static void |
| df_rd_free (void) |
| { |
| struct df_rd_problem_data *problem_data |
| = (struct df_rd_problem_data *) df_rd->problem_data; |
| |
| if (problem_data) |
| { |
| bitmap_obstack_release (&problem_data->rd_bitmaps); |
| |
| df_rd->block_info_size = 0; |
| free (df_rd->block_info); |
| df_rd->block_info = NULL; |
| free (df_rd->problem_data); |
| } |
| free (df_rd); |
| } |
| |
| |
| /* Debugging info. */ |
| |
| static void |
| df_rd_start_dump (FILE *file) |
| { |
| struct df_rd_problem_data *problem_data |
| = (struct df_rd_problem_data *) df_rd->problem_data; |
| unsigned int m = DF_REG_SIZE (df); |
| unsigned int regno; |
| |
| if (!df_rd->block_info) |
| return; |
| |
| fprintf (file, ";; Reaching defs:\n"); |
| |
| fprintf (file, ";; sparse invalidated \t"); |
| dump_bitmap (file, &problem_data->sparse_invalidated_by_call); |
| fprintf (file, ";; dense invalidated \t"); |
| dump_bitmap (file, &problem_data->dense_invalidated_by_call); |
| |
| fprintf (file, ";; reg->defs[] map:\t"); |
| for (regno = 0; regno < m; regno++) |
| if (DF_DEFS_COUNT (regno)) |
| fprintf (file, "%d[%d,%d] ", regno, |
| DF_DEFS_BEGIN (regno), |
| DF_DEFS_BEGIN (regno) + DF_DEFS_COUNT (regno) - 1); |
| fprintf (file, "\n"); |
| } |
| |
| |
| static void |
| df_rd_dump_defs_set (bitmap defs_set, const char *prefix, FILE *file) |
| { |
| bitmap_head tmp; |
| unsigned int regno; |
| unsigned int m = DF_REG_SIZE (df); |
| bool first_reg = true; |
| |
| fprintf (file, "%s\t(%d) ", prefix, (int) bitmap_count_bits (defs_set)); |
| |
| bitmap_initialize (&tmp, &df_bitmap_obstack); |
| for (regno = 0; regno < m; regno++) |
| { |
| if (HARD_REGISTER_NUM_P (regno) |
| && (df->changeable_flags & DF_NO_HARD_REGS)) |
| continue; |
| bitmap_set_range (&tmp, DF_DEFS_BEGIN (regno), DF_DEFS_COUNT (regno)); |
| bitmap_and_into (&tmp, defs_set); |
| if (! bitmap_empty_p (&tmp)) |
| { |
| bitmap_iterator bi; |
| unsigned int ix; |
| bool first_def = true; |
| |
| if (! first_reg) |
| fprintf (file, ","); |
| first_reg = false; |
| |
| fprintf (file, "%u[", regno); |
| EXECUTE_IF_SET_IN_BITMAP (&tmp, 0, ix, bi) |
| { |
| fprintf (file, "%s%u", first_def ? "" : ",", ix); |
| first_def = false; |
| } |
| fprintf (file, "]"); |
| } |
| bitmap_clear (&tmp); |
| } |
| |
| fprintf (file, "\n"); |
| bitmap_clear (&tmp); |
| } |
| |
| /* Debugging info at top of bb. */ |
| |
| static void |
| df_rd_top_dump (basic_block bb, FILE *file) |
| { |
| struct df_rd_bb_info *bb_info = df_rd_get_bb_info (bb->index); |
| if (!bb_info) |
| return; |
| |
| df_rd_dump_defs_set (&bb_info->in, ";; rd in ", file); |
| df_rd_dump_defs_set (&bb_info->gen, ";; rd gen ", file); |
| df_rd_dump_defs_set (&bb_info->kill, ";; rd kill", file); |
| } |
| |
| |
| /* Debugging info at bottom of bb. */ |
| |
| static void |
| df_rd_bottom_dump (basic_block bb, FILE *file) |
| { |
| struct df_rd_bb_info *bb_info = df_rd_get_bb_info (bb->index); |
| if (!bb_info) |
| return; |
| |
| df_rd_dump_defs_set (&bb_info->out, ";; rd out ", file); |
| } |
| |
| /* All of the information associated with every instance of the problem. */ |
| |
| static const struct df_problem problem_RD = |
| { |
| DF_RD, /* Problem id. */ |
| DF_FORWARD, /* Direction. */ |
| df_rd_alloc, /* Allocate the problem specific data. */ |
| NULL, /* Reset global information. */ |
| df_rd_free_bb_info, /* Free basic block info. */ |
| df_rd_local_compute, /* Local compute function. */ |
| df_rd_init_solution, /* Init the solution specific data. */ |
| df_worklist_dataflow, /* Worklist solver. */ |
| NULL, /* Confluence operator 0. */ |
| df_rd_confluence_n, /* Confluence operator n. */ |
| df_rd_transfer_function, /* Transfer function. */ |
| NULL, /* Finalize function. */ |
| df_rd_free, /* Free all of the problem information. */ |
| df_rd_free, /* Remove this problem from the stack of dataflow problems. */ |
| df_rd_start_dump, /* Debugging. */ |
| df_rd_top_dump, /* Debugging start block. */ |
| df_rd_bottom_dump, /* Debugging end block. */ |
| NULL, /* Debugging start insn. */ |
| NULL, /* Debugging end insn. */ |
| NULL, /* Incremental solution verify start. */ |
| NULL, /* Incremental solution verify end. */ |
| NULL, /* Dependent problem. */ |
| sizeof (struct df_rd_bb_info),/* Size of entry of block_info array. */ |
| TV_DF_RD, /* Timing variable. */ |
| true /* Reset blocks on dropping out of blocks_to_analyze. */ |
| }; |
| |
| |
| |
| /* Create a new RD instance and add it to the existing instance |
| of DF. */ |
| |
| void |
| df_rd_add_problem (void) |
| { |
| df_add_problem (&problem_RD); |
| } |
| |
| |
| |
| /*---------------------------------------------------------------------------- |
| LIVE REGISTERS |
| |
| Find the locations in the function where any use of a pseudo can |
| reach in the backwards direction. In and out bitvectors are built |
| for each basic block. The regno is used to index into these sets. |
| See df.h for details. |
| ----------------------------------------------------------------------------*/ |
| |
| /* Private data used to verify the solution for this problem. */ |
| struct df_lr_problem_data |
| { |
| bitmap_head *in; |
| bitmap_head *out; |
| /* An obstack for the bitmaps we need for this problem. */ |
| bitmap_obstack lr_bitmaps; |
| }; |
| |
| /* Free basic block info. */ |
| |
| static void |
| df_lr_free_bb_info (basic_block bb ATTRIBUTE_UNUSED, |
| void *vbb_info) |
| { |
| struct df_lr_bb_info *bb_info = (struct df_lr_bb_info *) vbb_info; |
| if (bb_info) |
| { |
| bitmap_clear (&bb_info->use); |
| bitmap_clear (&bb_info->def); |
| bitmap_clear (&bb_info->in); |
| bitmap_clear (&bb_info->out); |
| } |
| } |
| |
| |
| /* Allocate or reset bitmaps for DF_LR blocks. The solution bits are |
| not touched unless the block is new. */ |
| |
| static void |
| df_lr_alloc (bitmap all_blocks ATTRIBUTE_UNUSED) |
| { |
| unsigned int bb_index; |
| bitmap_iterator bi; |
| struct df_lr_problem_data *problem_data; |
| |
| df_grow_bb_info (df_lr); |
| if (df_lr->problem_data) |
| problem_data = (struct df_lr_problem_data *) df_lr->problem_data; |
| else |
| { |
| problem_data = XNEW (struct df_lr_problem_data); |
| df_lr->problem_data = problem_data; |
| |
| problem_data->out = NULL; |
| problem_data->in = NULL; |
| bitmap_obstack_initialize (&problem_data->lr_bitmaps); |
| } |
| |
| EXECUTE_IF_SET_IN_BITMAP (df_lr->out_of_date_transfer_functions, 0, bb_index, bi) |
| { |
| struct df_lr_bb_info *bb_info = df_lr_get_bb_info (bb_index); |
| |
| /* When bitmaps are already initialized, just clear them. */ |
| if (bb_info->use.obstack) |
| { |
| bitmap_clear (&bb_info->def); |
| bitmap_clear (&bb_info->use); |
| } |
| else |
| { |
| bitmap_initialize (&bb_info->use, &problem_data->lr_bitmaps); |
| bitmap_initialize (&bb_info->def, &problem_data->lr_bitmaps); |
| bitmap_initialize (&bb_info->in, &problem_data->lr_bitmaps); |
| bitmap_initialize (&bb_info->out, &problem_data->lr_bitmaps); |
| } |
| } |
| |
| df_lr->optional_p = false; |
| } |
| |
| |
| /* Reset the global solution for recalculation. */ |
| |
| static void |
| df_lr_reset (bitmap all_blocks) |
| { |
| unsigned int bb_index; |
| bitmap_iterator bi; |
| |
| EXECUTE_IF_SET_IN_BITMAP (all_blocks, 0, bb_index, bi) |
| { |
| struct df_lr_bb_info *bb_info = df_lr_get_bb_info (bb_index); |
| gcc_assert (bb_info); |
| bitmap_clear (&bb_info->in); |
| bitmap_clear (&bb_info->out); |
| } |
| } |
| |
| |
| /* Compute local live register info for basic block BB. */ |
| |
| static void |
| df_lr_bb_local_compute (unsigned int bb_index) |
| { |
| basic_block bb = BASIC_BLOCK_FOR_FN (cfun, bb_index); |
| struct df_lr_bb_info *bb_info = df_lr_get_bb_info (bb_index); |
| rtx_insn *insn; |
| df_ref def, use; |
| |
| /* Process the registers set in an exception handler. */ |
| FOR_EACH_ARTIFICIAL_DEF (def, bb_index) |
| if ((DF_REF_FLAGS (def) & DF_REF_AT_TOP) == 0) |
| { |
| unsigned int dregno = DF_REF_REGNO (def); |
| bitmap_set_bit (&bb_info->def, dregno); |
| bitmap_clear_bit (&bb_info->use, dregno); |
| } |
| |
| /* Process the hardware registers that are always live. */ |
| FOR_EACH_ARTIFICIAL_USE (use, bb_index) |
| /* Add use to set of uses in this BB. */ |
| if ((DF_REF_FLAGS (use) & DF_REF_AT_TOP) == 0) |
| bitmap_set_bit (&bb_info->use, DF_REF_REGNO (use)); |
| |
| FOR_BB_INSNS_REVERSE (bb, insn) |
| { |
| if (!NONDEBUG_INSN_P (insn)) |
| continue; |
| |
| df_insn_info *insn_info = DF_INSN_INFO_GET (insn); |
| FOR_EACH_INSN_INFO_DEF (def, insn_info) |
| /* If the def is to only part of the reg, it does |
| not kill the other defs that reach here. */ |
| if (!(DF_REF_FLAGS (def) & (DF_REF_PARTIAL | DF_REF_CONDITIONAL))) |
| { |
| unsigned int dregno = DF_REF_REGNO (def); |
| bitmap_set_bit (&bb_info->def, dregno); |
| bitmap_clear_bit (&bb_info->use, dregno); |
| } |
| |
| FOR_EACH_INSN_INFO_USE (use, insn_info) |
| /* Add use to set of uses in this BB. */ |
| bitmap_set_bit (&bb_info->use, DF_REF_REGNO (use)); |
| } |
| |
| /* Process the registers set in an exception handler or the hard |
| frame pointer if this block is the target of a non local |
| goto. */ |
| FOR_EACH_ARTIFICIAL_DEF (def, bb_index) |
| if (DF_REF_FLAGS (def) & DF_REF_AT_TOP) |
| { |
| unsigned int dregno = DF_REF_REGNO (def); |
| bitmap_set_bit (&bb_info->def, dregno); |
| bitmap_clear_bit (&bb_info->use, dregno); |
| } |
| |
| #ifdef EH_USES |
| /* Process the uses that are live into an exception handler. */ |
| FOR_EACH_ARTIFICIAL_USE (use, bb_index) |
| /* Add use to set of uses in this BB. */ |
| if (DF_REF_FLAGS (use) & DF_REF_AT_TOP) |
| bitmap_set_bit (&bb_info->use, DF_REF_REGNO (use)); |
| #endif |
| |
| /* If the df_live problem is not defined, such as at -O0 and -O1, we |
| still need to keep the luids up to date. This is normally done |
| in the df_live problem since this problem has a forwards |
| scan. */ |
| if (!df_live) |
| df_recompute_luids (bb); |
| } |
| |
| |
| /* Compute local live register info for each basic block within BLOCKS. */ |
| |
| static void |
| df_lr_local_compute (bitmap all_blocks ATTRIBUTE_UNUSED) |
| { |
| unsigned int bb_index, i; |
| bitmap_iterator bi; |
| |
| bitmap_clear (&df->hardware_regs_used); |
| |
| /* The all-important stack pointer must always be live. */ |
| bitmap_set_bit (&df->hardware_regs_used, STACK_POINTER_REGNUM); |
| |
| /* Global regs are always live, too. */ |
| for (i = 0; i < FIRST_PSEUDO_REGISTER; i++) |
| if (global_regs[i]) |
| bitmap_set_bit (&df->hardware_regs_used, i); |
| |
| /* Before reload, there are a few registers that must be forced |
| live everywhere -- which might not already be the case for |
| blocks within infinite loops. */ |
| if (!reload_completed) |
| { |
| unsigned int pic_offset_table_regnum = PIC_OFFSET_TABLE_REGNUM; |
| /* Any reference to any pseudo before reload is a potential |
| reference of the frame pointer. */ |
| bitmap_set_bit (&df->hardware_regs_used, FRAME_POINTER_REGNUM); |
| |
| /* Pseudos with argument area equivalences may require |
| reloading via the argument pointer. */ |
| if (FRAME_POINTER_REGNUM != ARG_POINTER_REGNUM |
| && fixed_regs[ARG_POINTER_REGNUM]) |
| bitmap_set_bit (&df->hardware_regs_used, ARG_POINTER_REGNUM); |
| |
| /* Any constant, or pseudo with constant equivalences, may |
| require reloading from memory using the pic register. */ |
| if (pic_offset_table_regnum != INVALID_REGNUM |
| && fixed_regs[pic_offset_table_regnum]) |
| bitmap_set_bit (&df->hardware_regs_used, pic_offset_table_regnum); |
| } |
| |
| EXECUTE_IF_SET_IN_BITMAP (df_lr->out_of_date_transfer_functions, 0, bb_index, bi) |
| { |
| if (bb_index == EXIT_BLOCK) |
| { |
| /* The exit block is special for this problem and its bits are |
| computed from thin air. */ |
| struct df_lr_bb_info *bb_info = df_lr_get_bb_info (EXIT_BLOCK); |
| bitmap_copy (&bb_info->use, df->exit_block_uses); |
| } |
| else |
| df_lr_bb_local_compute (bb_index); |
| } |
| |
| bitmap_clear (df_lr->out_of_date_transfer_functions); |
| } |
| |
| |
| /* Initialize the solution vectors. */ |
| |
| static void |
| df_lr_init (bitmap all_blocks) |
| { |
| unsigned int bb_index; |
| bitmap_iterator bi; |
| |
| EXECUTE_IF_SET_IN_BITMAP (all_blocks, 0, bb_index, bi) |
| { |
| struct df_lr_bb_info *bb_info = df_lr_get_bb_info (bb_index); |
| bitmap_copy (&bb_info->in, &bb_info->use); |
| bitmap_clear (&bb_info->out); |
| } |
| } |
| |
| |
| /* Confluence function that processes infinite loops. This might be a |
| noreturn function that throws. And even if it isn't, getting the |
| unwind info right helps debugging. */ |
| static void |
| df_lr_confluence_0 (basic_block bb) |
| { |
| bitmap op1 = &df_lr_get_bb_info (bb->index)->out; |
| if (bb != EXIT_BLOCK_PTR_FOR_FN (cfun)) |
| bitmap_copy (op1, &df->hardware_regs_used); |
| } |
| |
| |
| /* Confluence function that ignores fake edges. */ |
| |
| static bool |
| df_lr_confluence_n (edge e) |
| { |
| bitmap op1 = &df_lr_get_bb_info (e->src->index)->out; |
| bitmap op2 = &df_lr_get_bb_info (e->dest->index)->in; |
| bool changed = false; |
| |
| /* Call-clobbered registers die across exception and call edges. */ |
| /* ??? Abnormal call edges ignored for the moment, as this gets |
| confused by sibling call edges, which crashes reg-stack. */ |
| if (e->flags & EDGE_EH) |
| changed = bitmap_ior_and_compl_into (op1, op2, regs_invalidated_by_call_regset); |
| else |
| changed = bitmap_ior_into (op1, op2); |
| |
| changed |= bitmap_ior_into (op1, &df->hardware_regs_used); |
| return changed; |
| } |
| |
| |
| /* Transfer function. */ |
| |
| static bool |
| df_lr_transfer_function (int bb_index) |
| { |
| struct df_lr_bb_info *bb_info = df_lr_get_bb_info (bb_index); |
| bitmap in = &bb_info->in; |
| bitmap out = &bb_info->out; |
| bitmap use = &bb_info->use; |
| bitmap def = &bb_info->def; |
| |
| return bitmap_ior_and_compl (in, use, out, def); |
| } |
| |
| |
| /* Run the fast dce as a side effect of building LR. */ |
| |
| static void |
| df_lr_finalize (bitmap all_blocks) |
| { |
| df_lr->solutions_dirty = false; |
| if (df->changeable_flags & DF_LR_RUN_DCE) |
| { |
| run_fast_df_dce (); |
| |
| /* If dce deletes some instructions, we need to recompute the lr |
| solution before proceeding further. The problem is that fast |
| dce is a pessimestic dataflow algorithm. In the case where |
| it deletes a statement S inside of a loop, the uses inside of |
| S may not be deleted from the dataflow solution because they |
| were carried around the loop. While it is conservatively |
| correct to leave these extra bits, the standards of df |
| require that we maintain the best possible (least fixed |
| point) solution. The only way to do that is to redo the |
| iteration from the beginning. See PR35805 for an |
| example. */ |
| if (df_lr->solutions_dirty) |
| { |
| df_clear_flags (DF_LR_RUN_DCE); |
| df_lr_alloc (all_blocks); |
| df_lr_local_compute (all_blocks); |
| df_worklist_dataflow (df_lr, all_blocks, df->postorder, df->n_blocks); |
| df_lr_finalize (all_blocks); |
| df_set_flags (DF_LR_RUN_DCE); |
| } |
| } |
| } |
| |
| |
| /* Free all storage associated with the problem. */ |
| |
| static void |
| df_lr_free (void) |
| { |
| struct df_lr_problem_data *problem_data |
| = (struct df_lr_problem_data *) df_lr->problem_data; |
| if (df_lr->block_info) |
| { |
| |
| df_lr->block_info_size = 0; |
| free (df_lr->block_info); |
| df_lr->block_info = NULL; |
| bitmap_obstack_release (&problem_data->lr_bitmaps); |
| free (df_lr->problem_data); |
| df_lr->problem_data = NULL; |
| } |
| |
| BITMAP_FREE (df_lr->out_of_date_transfer_functions); |
| free (df_lr); |
| } |
| |
| |
| /* Debugging info at top of bb. */ |
| |
| static void |
| df_lr_top_dump (basic_block bb, FILE *file) |
| { |
| struct df_lr_bb_info *bb_info = df_lr_get_bb_info (bb->index); |
| struct df_lr_problem_data *problem_data; |
| if (!bb_info) |
| return; |
| |
| fprintf (file, ";; lr in \t"); |
| df_print_regset (file, &bb_info->in); |
| if (df_lr->problem_data) |
| { |
| problem_data = (struct df_lr_problem_data *)df_lr->problem_data; |
| if (problem_data->in) |
| { |
| fprintf (file, ";; old in \t"); |
| df_print_regset (file, &problem_data->in[bb->index]); |
| } |
| } |
| fprintf (file, ";; lr use \t"); |
| df_print_regset (file, &bb_info->use); |
| fprintf (file, ";; lr def \t"); |
| df_print_regset (file, &bb_info->def); |
| } |
| |
| |
| /* Debugging info at bottom of bb. */ |
| |
| static void |
| df_lr_bottom_dump (basic_block bb, FILE *file) |
| { |
| struct df_lr_bb_info *bb_info = df_lr_get_bb_info (bb->index); |
| struct df_lr_problem_data *problem_data; |
| if (!bb_info) |
| return; |
| |
| fprintf (file, ";; lr out \t"); |
| df_print_regset (file, &bb_info->out); |
| if (df_lr->problem_data) |
| { |
| problem_data = (struct df_lr_problem_data *)df_lr->problem_data; |
| if (problem_data->out) |
| { |
| fprintf (file, ";; old out \t"); |
| df_print_regset (file, &problem_data->out[bb->index]); |
| } |
| } |
| } |
| |
| |
| /* Build the datastructure to verify that the solution to the dataflow |
| equations is not dirty. */ |
| |
| static void |
| df_lr_verify_solution_start (void) |
| { |
| basic_block bb; |
| struct df_lr_problem_data *problem_data; |
| if (df_lr->solutions_dirty) |
| return; |
| |
| /* Set it true so that the solution is recomputed. */ |
| df_lr->solutions_dirty = true; |
| |
| problem_data = (struct df_lr_problem_data *)df_lr->problem_data; |
| problem_data->in = XNEWVEC (bitmap_head, last_basic_block_for_fn (cfun)); |
| problem_data->out = XNEWVEC (bitmap_head, last_basic_block_for_fn (cfun)); |
| |
| FOR_ALL_BB_FN (bb, cfun) |
| { |
| bitmap_initialize (&problem_data->in[bb->index], &problem_data->lr_bitmaps); |
| bitmap_initialize (&problem_data->out[bb->index], &problem_data->lr_bitmaps); |
| bitmap_copy (&problem_data->in[bb->index], DF_LR_IN (bb)); |
| bitmap_copy (&problem_data->out[bb->index], DF_LR_OUT (bb)); |
| } |
| } |
| |
| |
| /* Compare the saved datastructure and the new solution to the dataflow |
| equations. */ |
| |
| static void |
| df_lr_verify_solution_end (void) |
| { |
| struct df_lr_problem_data *problem_data; |
| basic_block bb; |
| |
| problem_data = (struct df_lr_problem_data *)df_lr->problem_data; |
| |
| if (!problem_data->out) |
| return; |
| |
| if (df_lr->solutions_dirty) |
| /* Do not check if the solution is still dirty. See the comment |
| in df_lr_finalize for details. */ |
| df_lr->solutions_dirty = false; |
| else |
| FOR_ALL_BB_FN (bb, cfun) |
| { |
| if ((!bitmap_equal_p (&problem_data->in[bb->index], DF_LR_IN (bb))) |
| || (!bitmap_equal_p (&problem_data->out[bb->index], DF_LR_OUT (bb)))) |
| { |
| /*df_dump (stderr);*/ |
| gcc_unreachable (); |
| } |
| } |
| |
| /* Cannot delete them immediately because you may want to dump them |
| if the comparison fails. */ |
| FOR_ALL_BB_FN (bb, cfun) |
| { |
| bitmap_clear (&problem_data->in[bb->index]); |
| bitmap_clear (&problem_data->out[bb->index]); |
| } |
| |
| free (problem_data->in); |
| free (problem_data->out); |
| problem_data->in = NULL; |
| problem_data->out = NULL; |
| } |
| |
| |
| /* All of the information associated with every instance of the problem. */ |
| |
| static const struct df_problem problem_LR = |
| { |
| DF_LR, /* Problem id. */ |
| DF_BACKWARD, /* Direction. */ |
| df_lr_alloc, /* Allocate the problem specific data. */ |
| df_lr_reset, /* Reset global information. */ |
| df_lr_free_bb_info, /* Free basic block info. */ |
| df_lr_local_compute, /* Local compute function. */ |
| df_lr_init, /* Init the solution specific data. */ |
| df_worklist_dataflow, /* Worklist solver. */ |
| df_lr_confluence_0, /* Confluence operator 0. */ |
| df_lr_confluence_n, /* Confluence operator n. */ |
| df_lr_transfer_function, /* Transfer function. */ |
| df_lr_finalize, /* Finalize function. */ |
| df_lr_free, /* Free all of the problem information. */ |
| NULL, /* Remove this problem from the stack of dataflow problems. */ |
| NULL, /* Debugging. */ |
| df_lr_top_dump, /* Debugging start block. */ |
| df_lr_bottom_dump, /* Debugging end block. */ |
| NULL, /* Debugging start insn. */ |
| NULL, /* Debugging end insn. */ |
| df_lr_verify_solution_start,/* Incremental solution verify start. */ |
| df_lr_verify_solution_end, /* Incremental solution verify end. */ |
| NULL, /* Dependent problem. */ |
| sizeof (struct df_lr_bb_info),/* Size of entry of block_info array. */ |
| TV_DF_LR, /* Timing variable. */ |
| false /* Reset blocks on dropping out of blocks_to_analyze. */ |
| }; |
| |
| |
| /* Create a new DATAFLOW instance and add it to an existing instance |
| of DF. The returned structure is what is used to get at the |
| solution. */ |
| |
| void |
| df_lr_add_problem (void) |
| { |
| df_add_problem (&problem_LR); |
| /* These will be initialized when df_scan_blocks processes each |
| block. */ |
| df_lr->out_of_date_transfer_functions = BITMAP_ALLOC (&df_bitmap_obstack); |
| } |
| |
| |
| /* Verify that all of the lr related info is consistent and |
| correct. */ |
| |
| void |
| df_lr_verify_transfer_functions (void) |
| { |
| basic_block bb; |
| bitmap_head saved_def; |
| bitmap_head saved_use; |
| bitmap_head all_blocks; |
| |
| if (!df) |
| return; |
| |
| bitmap_initialize (&saved_def, &bitmap_default_obstack); |
| bitmap_initialize (&saved_use, &bitmap_default_obstack); |
| bitmap_initialize (&all_blocks, &bitmap_default_obstack); |
| |
| FOR_ALL_BB_FN (bb, cfun) |
| { |
| struct df_lr_bb_info *bb_info = df_lr_get_bb_info (bb->index); |
| bitmap_set_bit (&all_blocks, bb->index); |
| |
| if (bb_info) |
| { |
| /* Make a copy of the transfer functions and then compute |
| new ones to see if the transfer functions have |
| changed. */ |
| if (!bitmap_bit_p (df_lr->out_of_date_transfer_functions, |
| bb->index)) |
| { |
| bitmap_copy (&saved_def, &bb_info->def); |
| bitmap_copy (&saved_use, &bb_info->use); |
| bitmap_clear (&bb_info->def); |
| bitmap_clear (&bb_info->use); |
| |
| df_lr_bb_local_compute (bb->index); |
| gcc_assert (bitmap_equal_p (&saved_def, &bb_info->def)); |
| gcc_assert (bitmap_equal_p (&saved_use, &bb_info->use)); |
| } |
| } |
| else |
| { |
| /* If we do not have basic block info, the block must be in |
| the list of dirty blocks or else some one has added a |
| block behind our backs. */ |
| gcc_assert (bitmap_bit_p (df_lr->out_of_date_transfer_functions, |
| bb->index)); |
| } |
| /* Make sure no one created a block without following |
| procedures. */ |
| gcc_assert (df_scan_get_bb_info (bb->index)); |
| } |
| |
| /* Make sure there are no dirty bits in blocks that have been deleted. */ |
| gcc_assert (!bitmap_intersect_compl_p (df_lr->out_of_date_transfer_functions, |
| &all_blocks)); |
| |
| bitmap_clear (&saved_def); |
| bitmap_clear (&saved_use); |
| bitmap_clear (&all_blocks); |
| } |
| |
| |
| |
| /*---------------------------------------------------------------------------- |
| LIVE AND MAY-INITIALIZED REGISTERS. |
| |
| This problem first computes the IN and OUT bitvectors for the |
| may-initialized registers problems, which is a forward problem. |
| It gives the set of registers for which we MAY have an available |
| definition, i.e. for which there is an available definition on |
| at least one path from the entry block to the entry/exit of a |
| basic block. Sets generate a definition, while clobbers kill |
| a definition. |
| |
| In and out bitvectors are built for each basic block and are indexed by |
| regnum (see df.h for details). In and out bitvectors in struct |
| df_live_bb_info actually refers to the may-initialized problem; |
| |
| Then, the in and out sets for the LIVE problem itself are computed. |
| These are the logical AND of the IN and OUT sets from the LR problem |
| and the may-initialized problem. |
| ----------------------------------------------------------------------------*/ |
| |
| /* Private data used to verify the solution for this problem. */ |
| struct df_live_problem_data |
| { |
| bitmap_head *in; |
| bitmap_head *out; |
| /* An obstack for the bitmaps we need for this problem. */ |
| bitmap_obstack live_bitmaps; |
| }; |
| |
| /* Scratch var used by transfer functions. This is used to implement |
| an optimization to reduce the amount of space used to compute the |
| combined lr and live analysis. */ |
| static bitmap_head df_live_scratch; |
| |
| |
| /* Free basic block info. */ |
| |
| static void |
| df_live_free_bb_info (basic_block bb ATTRIBUTE_UNUSED, |
| void *vbb_info) |
| { |
| struct df_live_bb_info *bb_info = (struct df_live_bb_info *) vbb_info; |
| if (bb_info) |
| { |
| bitmap_clear (&bb_info->gen); |
| bitmap_clear (&bb_info->kill); |
| bitmap_clear (&bb_info->in); |
| bitmap_clear (&bb_info->out); |
| } |
| } |
| |
| |
| /* Allocate or reset bitmaps for DF_LIVE blocks. The solution bits are |
| not touched unless the block is new. */ |
| |
| static void |
| df_live_alloc (bitmap all_blocks ATTRIBUTE_UNUSED) |
| { |
| unsigned int bb_index; |
| bitmap_iterator bi; |
| struct df_live_problem_data *problem_data; |
| |
| if (df_live->problem_data) |
| problem_data = (struct df_live_problem_data *) df_live->problem_data; |
| else |
| { |
| problem_data = XNEW (struct df_live_problem_data); |
| df_live->problem_data = problem_data; |
| |
| problem_data->out = NULL; |
| problem_data->in = NULL; |
| bitmap_obstack_initialize (&problem_data->live_bitmaps); |
| bitmap_initialize (&df_live_scratch, &problem_data->live_bitmaps); |
| } |
| |
| df_grow_bb_info (df_live); |
| |
| EXECUTE_IF_SET_IN_BITMAP (df_live->out_of_date_transfer_functions, 0, bb_index, bi) |
| { |
| struct df_live_bb_info *bb_info = df_live_get_bb_info (bb_index); |
| |
| /* When bitmaps are already initialized, just clear them. */ |
| if (bb_info->kill.obstack) |
| { |
| bitmap_clear (&bb_info->kill); |
| bitmap_clear (&bb_info->gen); |
| } |
| else |
| { |
| bitmap_initialize (&bb_info->kill, &problem_data->live_bitmaps); |
| bitmap_initialize (&bb_info->gen, &problem_data->live_bitmaps); |
| bitmap_initialize (&bb_info->in, &problem_data->live_bitmaps); |
| bitmap_initialize (&bb_info->out, &problem_data->live_bitmaps); |
| } |
| } |
| df_live->optional_p = (optimize <= 1); |
| } |
| |
| |
| /* Reset the global solution for recalculation. */ |
| |
| static void |
| df_live_reset (bitmap all_blocks) |
| { |
| unsigned int bb_index; |
| bitmap_iterator bi; |
| |
| EXECUTE_IF_SET_IN_BITMAP (all_blocks, 0, bb_index, bi) |
| { |
| struct df_live_bb_info *bb_info = df_live_get_bb_info (bb_index); |
| gcc_assert (bb_info); |
| bitmap_clear (&bb_info->in); |
| bitmap_clear (&bb_info->out); |
| } |
| } |
| |
| |
| /* Compute local uninitialized register info for basic block BB. */ |
| |
| static void |
| df_live_bb_local_compute (unsigned int bb_index) |
| { |
| basic_block bb = BASIC_BLOCK_FOR_FN (cfun, bb_index); |
| struct df_live_bb_info *bb_info = df_live_get_bb_info (bb_index); |
| rtx_insn *insn; |
| df_ref def; |
| int luid = 0; |
| |
| FOR_BB_INSNS (bb, insn) |
| { |
| unsigned int uid = INSN_UID (insn); |
| struct df_insn_info *insn_info = DF_INSN_UID_GET (uid); |
| |
| /* Inserting labels does not always trigger the incremental |
| rescanning. */ |
| if (!insn_info) |
| { |
| gcc_assert (!INSN_P (insn)); |
| insn_info = df_insn_create_insn_record (insn); |
| } |
| |
| DF_INSN_INFO_LUID (insn_info) = luid; |
| if (!INSN_P (insn)) |
| continue; |
| |
| luid++; |
| FOR_EACH_INSN_INFO_DEF (def, insn_info) |
| { |
| unsigned int regno = DF_REF_REGNO (def); |
| |
| if (DF_REF_FLAGS_IS_SET (def, |
| DF_REF_PARTIAL | DF_REF_CONDITIONAL)) |
| /* All partial or conditional def |
| seen are included in the gen set. */ |
| bitmap_set_bit (&bb_info->gen, regno); |
| else if (DF_REF_FLAGS_IS_SET (def, DF_REF_MUST_CLOBBER)) |
| /* Only must clobbers for the entire reg destroy the |
| value. */ |
| bitmap_set_bit (&bb_info->kill, regno); |
| else if (! DF_REF_FLAGS_IS_SET (def, DF_REF_MAY_CLOBBER)) |
| bitmap_set_bit (&bb_info->gen, regno); |
| } |
| } |
| |
| FOR_EACH_ARTIFICIAL_DEF (def, bb_index) |
| bitmap_set_bit (&bb_info->gen, DF_REF_REGNO (def)); |
| } |
| |
| |
| /* Compute local uninitialized register info. */ |
| |
| static void |
| df_live_local_compute (bitmap all_blocks ATTRIBUTE_UNUSED) |
| { |
| unsigned int bb_index; |
| bitmap_iterator bi; |
| |
| df_grow_insn_info (); |
| |
| EXECUTE_IF_SET_IN_BITMAP (df_live->out_of_date_transfer_functions, |
| 0, bb_index, bi) |
| { |
| df_live_bb_local_compute (bb_index); |
| } |
| |
| bitmap_clear (df_live->out_of_date_transfer_functions); |
| } |
| |
| |
| /* Initialize the solution vectors. */ |
| |
| static void |
| df_live_init (bitmap all_blocks) |
| { |
| unsigned int bb_index; |
| bitmap_iterator bi; |
| |
| EXECUTE_IF_SET_IN_BITMAP (all_blocks, 0, bb_index, bi) |
| { |
| struct df_live_bb_info *bb_info = df_live_get_bb_info (bb_index); |
| struct df_lr_bb_info *bb_lr_info = df_lr_get_bb_info (bb_index); |
| |
| /* No register may reach a location where it is not used. Thus |
| we trim the rr result to the places where it is used. */ |
| bitmap_and (&bb_info->out, &bb_info->gen, &bb_lr_info->out); |
| bitmap_clear (&bb_info->in); |
| } |
| } |
| |
| /* Forward confluence function that ignores fake edges. */ |
| |
| static bool |
| df_live_confluence_n (edge e) |
| { |
| bitmap op1 = &df_live_get_bb_info (e->dest->index)->in; |
| bitmap op2 = &df_live_get_bb_info (e->src->index)->out; |
| |
| if (e->flags & EDGE_FAKE) |
| return false; |
| |
| return bitmap_ior_into (op1, op2); |
| } |
| |
| |
| /* Transfer function for the forwards may-initialized problem. */ |
| |
| static bool |
| df_live_transfer_function (int bb_index) |
| { |
| struct df_live_bb_info *bb_info = df_live_get_bb_info (bb_index); |
| struct df_lr_bb_info *bb_lr_info = df_lr_get_bb_info (bb_index); |
| bitmap in = &bb_info->in; |
| bitmap out = &bb_info->out; |
| bitmap gen = &bb_info->gen; |
| bitmap kill = &bb_info->kill; |
| |
| /* We need to use a scratch set here so that the value returned from this |
| function invocation properly reflects whether the sets changed in a |
| significant way; i.e. not just because the lr set was anded in. */ |
| bitmap_and (&df_live_scratch, gen, &bb_lr_info->out); |
| /* No register may reach a location where it is not used. Thus |
| we trim the rr result to the places where it is used. */ |
| bitmap_and_into (in, &bb_lr_info->in); |
| |
| return bitmap_ior_and_compl (out, &df_live_scratch, in, kill); |
| } |
| |
| |
| /* And the LR info with the may-initialized registers to produce the LIVE info. */ |
| |
| static void |
| df_live_finalize (bitmap all_blocks) |
| { |
| |
| if (df_live->solutions_dirty) |
| { |
| bitmap_iterator bi; |
| unsigned int bb_index; |
| |
| EXECUTE_IF_SET_IN_BITMAP (all_blocks, 0, bb_index, bi) |
| { |
| struct df_lr_bb_info *bb_lr_info = df_lr_get_bb_info (bb_index); |
| struct df_live_bb_info *bb_live_info = df_live_get_bb_info (bb_index); |
| |
| /* No register may reach a location where it is not used. Thus |
| we trim the rr result to the places where it is used. */ |
| bitmap_and_into (&bb_live_info->in, &bb_lr_info->in); |
| bitmap_and_into (&bb_live_info->out, &bb_lr_info->out); |
| } |
| |
| df_live->solutions_dirty = false; |
| } |
| } |
| |
| |
| /* Free all storage associated with the problem. */ |
| |
| static void |
| df_live_free (void) |
| { |
| struct df_live_problem_data *problem_data |
| = (struct df_live_problem_data *) df_live->problem_data; |
| if (df_live->block_info) |
| { |
| df_live->block_info_size = 0; |
| free (df_live->block_info); |
| df_live->block_info = NULL; |
| bitmap_clear (&df_live_scratch); |
| bitmap_obstack_release (&problem_data->live_bitmaps); |
| free (problem_data); |
| df_live->problem_data = NULL; |
| } |
| BITMAP_FREE (df_live->out_of_date_transfer_functions); |
| free (df_live); |
| } |
| |
| |
| /* Debugging info at top of bb. */ |
| |
| static void |
| df_live_top_dump (basic_block bb, FILE *file) |
| { |
| struct df_live_bb_info *bb_info = df_live_get_bb_info (bb->index); |
| struct df_live_problem_data *problem_data; |
| |
| if (!bb_info) |
| return; |
| |
| fprintf (file, ";; live in \t"); |
| df_print_regset (file, &bb_info->in); |
| if (df_live->problem_data) |
| { |
| problem_data = (struct df_live_problem_data *)df_live->problem_data; |
| if (problem_data->in) |
| { |
| fprintf (file, ";; old in \t"); |
| df_print_regset (file, &problem_data->in[bb->index]); |
| } |
| } |
| fprintf (file, ";; live gen \t"); |
| df_print_regset (file, &bb_info->gen); |
| fprintf (file, ";; live kill\t"); |
| df_print_regset (file, &bb_info->kill); |
| } |
| |
| |
| /* Debugging info at bottom of bb. */ |
| |
| static void |
| df_live_bottom_dump (basic_block bb, FILE *file) |
| { |
| struct df_live_bb_info *bb_info = df_live_get_bb_info (bb->index); |
| struct df_live_problem_data *problem_data; |
| |
| if (!bb_info) |
| return; |
| |
| fprintf (file, ";; live out \t"); |
| df_print_regset (file, &bb_info->out); |
| if (df_live->problem_data) |
| { |
| problem_data = (struct df_live_problem_data *)df_live->problem_data; |
| if (problem_data->out) |
| { |
| fprintf (file, ";; old out \t"); |
| df_print_regset (file, &problem_data->out[bb->index]); |
| } |
| } |
| } |
| |
| |
| /* Build the datastructure to verify that the solution to the dataflow |
| equations is not dirty. */ |
| |
| static void |
| df_live_verify_solution_start (void) |
| { |
| basic_block bb; |
| struct df_live_problem_data *problem_data; |
| if (df_live->solutions_dirty) |
| return; |
| |
| /* Set it true so that the solution is recomputed. */ |
| df_live->solutions_dirty = true; |
| |
| problem_data = (struct df_live_problem_data *)df_live->problem_data; |
| problem_data->in = XNEWVEC (bitmap_head, last_basic_block_for_fn (cfun)); |
| problem_data->out = XNEWVEC (bitmap_head, last_basic_block_for_fn (cfun)); |
| |
| FOR_ALL_BB_FN (bb, cfun) |
| { |
| bitmap_initialize (&problem_data->in[bb->index], &problem_data->live_bitmaps); |
| bitmap_initialize (&problem_data->out[bb->index], &problem_data->live_bitmaps); |
| bitmap_copy (&problem_data->in[bb->index], DF_LIVE_IN (bb)); |
| bitmap_copy (&problem_data->out[bb->index], DF_LIVE_OUT (bb)); |
| } |
| } |
| |
| |
| /* Compare the saved datastructure and the new solution to the dataflow |
| equations. */ |
| |
| static void |
| df_live_verify_solution_end (void) |
| { |
| struct df_live_problem_data *problem_data; |
| basic_block bb; |
| |
| problem_data = (struct df_live_problem_data *)df_live->problem_data; |
| if (!problem_data->out) |
| return; |
| |
| FOR_ALL_BB_FN (bb, cfun) |
| { |
| if ((!bitmap_equal_p (&problem_data->in[bb->index], DF_LIVE_IN (bb))) |
| || (!bitmap_equal_p (&problem_data->out[bb->index], DF_LIVE_OUT (bb)))) |
| { |
| /*df_dump (stderr);*/ |
| gcc_unreachable (); |
| } |
| } |
| |
| /* Cannot delete them immediately because you may want to dump them |
| if the comparison fails. */ |
| FOR_ALL_BB_FN (bb, cfun) |
| { |
| bitmap_clear (&problem_data->in[bb->index]); |
| bitmap_clear (&problem_data->out[bb->index]); |
| } |
| |
| free (problem_data->in); |
| free (problem_data->out); |
| free (problem_data); |
| df_live->problem_data = NULL; |
| } |
| |
| |
| /* All of the information associated with every instance of the problem. */ |
| |
| static const struct df_problem problem_LIVE = |
| { |
| DF_LIVE, /* Problem id. */ |
| DF_FORWARD, /* Direction. */ |
| df_live_alloc, /* Allocate the problem specific data. */ |
| df_live_reset, /* Reset global information. */ |
| df_live_free_bb_info, /* Free basic block info. */ |
| df_live_local_compute, /* Local compute function. */ |
| df_live_init, /* Init the solution specific data. */ |
| df_worklist_dataflow, /* Worklist solver. */ |
| NULL, /* Confluence operator 0. */ |
| df_live_confluence_n, /* Confluence operator n. */ |
| df_live_transfer_function, /* Transfer function. */ |
| df_live_finalize, /* Finalize function. */ |
| df_live_free, /* Free all of the problem information. */ |
| df_live_free, /* Remove this problem from the stack of dataflow problems. */ |
| NULL, /* Debugging. */ |
| df_live_top_dump, /* Debugging start block. */ |
| df_live_bottom_dump, /* Debugging end block. */ |
| NULL, /* Debugging start insn. */ |
| NULL, /* Debugging end insn. */ |
| df_live_verify_solution_start,/* Incremental solution verify start. */ |
| df_live_verify_solution_end, /* Incremental solution verify end. */ |
| &problem_LR, /* Dependent problem. */ |
| sizeof (struct df_live_bb_info),/* Size of entry of block_info array. */ |
| TV_DF_LIVE, /* Timing variable. */ |
| false /* Reset blocks on dropping out of blocks_to_analyze. */ |
| }; |
| |
| |
| /* Create a new DATAFLOW instance and add it to an existing instance |
| of DF. The returned structure is what is used to get at the |
| solution. */ |
| |
| void |
| df_live_add_problem (void) |
| { |
| df_add_problem (&problem_LIVE); |
| /* These will be initialized when df_scan_blocks processes each |
| block. */ |
| df_live->out_of_date_transfer_functions = BITMAP_ALLOC (&df_bitmap_obstack); |
| } |
| |
| |
| /* Set all of the blocks as dirty. This needs to be done if this |
| problem is added after all of the insns have been scanned. */ |
| |
| void |
| df_live_set_all_dirty (void) |
| { |
| basic_block bb; |
| FOR_ALL_BB_FN (bb, cfun) |
| bitmap_set_bit (df_live->out_of_date_transfer_functions, |
| bb->index); |
| } |
| |
| |
| /* Verify that all of the lr related info is consistent and |
| correct. */ |
| |
| void |
| df_live_verify_transfer_functions (void) |
| { |
| basic_block bb; |
| bitmap_head saved_gen; |
| bitmap_head saved_kill; |
| bitmap_head all_blocks; |
| |
| if (!df) |
| return; |
| |
| bitmap_initialize (&saved_gen, &bitmap_default_obstack); |
| bitmap_initialize (&saved_kill, &bitmap_default_obstack); |
| bitmap_initialize (&all_blocks, &bitmap_default_obstack); |
| |
| df_grow_insn_info (); |
| |
| FOR_ALL_BB_FN (bb, cfun) |
| { |
| struct df_live_bb_info *bb_info = df_live_get_bb_info (bb->index); |
| bitmap_set_bit (&all_blocks, bb->index); |
| |
| if (bb_info) |
| { |
| /* Make a copy of the transfer functions and then compute |
| new ones to see if the transfer functions have |
| changed. */ |
| if (!bitmap_bit_p (df_live->out_of_date_transfer_functions, |
| bb->index)) |
| { |
| bitmap_copy (&saved_gen, &bb_info->gen); |
| bitmap_copy (&saved_kill, &bb_info->kill); |
| bitmap_clear (&bb_info->gen); |
| bitmap_clear (&bb_info->kill); |
| |
| df_live_bb_local_compute (bb->index); |
| gcc_assert (bitmap_equal_p (&saved_gen, &bb_info->gen)); |
| gcc_assert (bitmap_equal_p (&saved_kill, &bb_info->kill)); |
| } |
| } |
| else |
| { |
| /* If we do not have basic block info, the block must be in |
| the list of dirty blocks or else some one has added a |
| block behind our backs. */ |
| gcc_assert (bitmap_bit_p (df_live->out_of_date_transfer_functions, |
| bb->index)); |
| } |
| /* Make sure no one created a block without following |
| procedures. */ |
| gcc_assert (df_scan_get_bb_info (bb->index)); |
| } |
| |
| /* Make sure there are no dirty bits in blocks that have been deleted. */ |
| gcc_assert (!bitmap_intersect_compl_p (df_live->out_of_date_transfer_functions, |
| &all_blocks)); |
| bitmap_clear (&saved_gen); |
| bitmap_clear (&saved_kill); |
| bitmap_clear (&all_blocks); |
| } |
| |
| /*---------------------------------------------------------------------------- |
| MUST-INITIALIZED REGISTERS. |
| ----------------------------------------------------------------------------*/ |
| |
| /* Private data used to verify the solution for this problem. */ |
| struct df_mir_problem_data |
| { |
| bitmap_head *in; |
| bitmap_head *out; |
| /* An obstack for the bitmaps we need for this problem. */ |
| bitmap_obstack mir_bitmaps; |
| }; |
| |
| |
| /* Free basic block info. */ |
| |
| static void |
| df_mir_free_bb_info (basic_block bb ATTRIBUTE_UNUSED, |
| void *vbb_info) |
| { |
| struct df_mir_bb_info *bb_info = (struct df_mir_bb_info *) vbb_info; |
| if (bb_info) |
| { |
| bitmap_clear (&bb_info->gen); |
| bitmap_clear (&bb_info->kill); |
| bitmap_clear (&bb_info->in); |
| bitmap_clear (&bb_info->out); |
| } |
| } |
| |
| |
| /* Allocate or reset bitmaps for DF_MIR blocks. The solution bits are |
| not touched unless the block is new. */ |
| |
| static void |
| df_mir_alloc (bitmap all_blocks) |
| { |
| unsigned int bb_index; |
| bitmap_iterator bi; |
| struct df_mir_problem_data *problem_data; |
| |
| if (df_mir->problem_data) |
| problem_data = (struct df_mir_problem_data *) df_mir->problem_data; |
| else |
| { |
| problem_data = XNEW (struct df_mir_problem_data); |
| df_mir->problem_data = problem_data; |
| |
| problem_data->out = NULL; |
| problem_data->in = NULL; |
| bitmap_obstack_initialize (&problem_data->mir_bitmaps); |
| } |
| |
| df_grow_bb_info (df_mir); |
| |
| EXECUTE_IF_SET_IN_BITMAP (all_blocks, 0, bb_index, bi) |
| { |
| struct df_mir_bb_info *bb_info = df_mir_get_bb_info (bb_index); |
| |
| /* When bitmaps are already initialized, just clear them. */ |
| if (bb_info->kill.obstack) |
| { |
| bitmap_clear (&bb_info->kill); |
| bitmap_clear (&bb_info->gen); |
| } |
| else |
| { |
| bitmap_initialize (&bb_info->kill, &problem_data->mir_bitmaps); |
| bitmap_initialize (&bb_info->gen, &problem_data->mir_bitmaps); |
| bitmap_initialize (&bb_info->in, &problem_data->mir_bitmaps); |
| bitmap_initialize (&bb_info->out, &problem_data->mir_bitmaps); |
| bitmap_set_range (&bb_info->in, 0, DF_REG_SIZE (df)); |
| bitmap_set_range (&bb_info->out, 0, DF_REG_SIZE (df)); |
| } |
| } |
| |
| df_mir->optional_p = 1; |
| } |
| |
| |
| /* Reset the global solution for recalculation. */ |
| |
| static void |
| df_mir_reset (bitmap all_blocks) |
| { |
| unsigned int bb_index; |
| bitmap_iterator bi; |
| |
| EXECUTE_IF_SET_IN_BITMAP (all_blocks, 0, bb_index, bi) |
| { |
| struct df_mir_bb_info *bb_info = df_mir_get_bb_info (bb_index); |
| |
| gcc_assert (bb_info); |
| |
| bitmap_clear (&bb_info->in); |
| bitmap_set_range (&bb_info->in, 0, DF_REG_SIZE (df)); |
| bitmap_clear (&bb_info->out); |
| bitmap_set_range (&bb_info->out, 0, DF_REG_SIZE (df)); |
| } |
| } |
| |
| |
| /* Compute local uninitialized register info for basic block BB. */ |
| |
| static void |
| df_mir_bb_local_compute (unsigned int bb_index) |
| { |
| basic_block bb = BASIC_BLOCK_FOR_FN (cfun, bb_index); |
| struct df_mir_bb_info *bb_info = df_mir_get_bb_info (bb_index); |
| rtx_insn *insn; |
| int luid = 0; |
| |
| /* Ignoring artificial defs is intentional: these often pretend that some |
| registers carry incoming arguments (when they are FUNCTION_ARG_REGNO) even |
| though they are not used for that. As a result, conservatively assume |
| they may be uninitialized. */ |
| |
| FOR_BB_INSNS (bb, insn) |
| { |
| unsigned int uid = INSN_UID (insn); |
| struct df_insn_info *insn_info = DF_INSN_UID_GET (uid); |
| |
| /* Inserting labels does not always trigger the incremental |
| rescanning. */ |
| if (!insn_info) |
| { |
| gcc_assert (!INSN_P (insn)); |
| insn_info = df_insn_create_insn_record (insn); |
| } |
| |
| DF_INSN_INFO_LUID (insn_info) = luid; |
| if (!INSN_P (insn)) |
| continue; |
| |
| luid++; |
| df_mir_simulate_one_insn (bb, insn, &bb_info->kill, &bb_info->gen); |
| } |
| } |
| |
| |
| /* Compute local uninitialized register info. */ |
| |
| static void |
| df_mir_local_compute (bitmap all_blocks) |
| { |
| unsigned int bb_index; |
| bitmap_iterator bi; |
| |
| df_grow_insn_info (); |
| |
| EXECUTE_IF_SET_IN_BITMAP (all_blocks, 0, bb_index, bi) |
| { |
| df_mir_bb_local_compute (bb_index); |
| } |
| } |
| |
| |
| /* Initialize the solution vectors. */ |
| |
| static void |
| df_mir_init (bitmap all_blocks) |
| { |
| df_mir_reset (all_blocks); |
| } |
| |
| |
| /* Initialize IN sets for blocks with no predecessors: when landing on such |
| blocks, assume all registers are uninitialized. */ |
| |
| static void |
| df_mir_confluence_0 (basic_block bb) |
| { |
| struct df_mir_bb_info *bb_info = df_mir_get_bb_info (bb->index); |
| |
| bitmap_clear (&bb_info->in); |
| } |
| |
| |
| /* Forward confluence function that ignores fake edges. */ |
| |
| static bool |
| df_mir_confluence_n (edge e) |
| { |
| bitmap op1 = &df_mir_get_bb_info (e->dest->index)->in; |
| bitmap op2 = &df_mir_get_bb_info (e->src->index)->out; |
| |
| if (e->flags & EDGE_FAKE) |
| return false; |
| |
| /* A register is must-initialized at the entry of a basic block iff it is |
| must-initialized at the exit of all the predecessors. */ |
| return bitmap_and_into (op1, op2); |
| } |
| |
| |
| /* Transfer function for the forwards must-initialized problem. */ |
| |
| static bool |
| df_mir_transfer_function (int bb_index) |
| { |
| struct df_mir_bb_info *bb_info = df_mir_get_bb_info (bb_index); |
| bitmap in = &bb_info->in; |
| bitmap out = &bb_info->out; |
| bitmap gen = &bb_info->gen; |
| bitmap kill = &bb_info->kill; |
| |
| return bitmap_ior_and_compl (out, gen, in, kill); |
| } |
| |
| |
| /* Free all storage associated with the problem. */ |
| |
| static void |
| df_mir_free (void) |
| { |
| struct df_mir_problem_data *problem_data |
| = (struct df_mir_problem_data *) df_mir->problem_data; |
| if (df_mir->block_info) |
| { |
| df_mir->block_info_size = 0; |
| free (df_mir->block_info); |
| df_mir->block_info = NULL; |
| bitmap_obstack_release (&problem_data->mir_bitmaps); |
| free (problem_data); |
| df_mir->problem_data = NULL; |
| } |
| free (df_mir); |
| } |
| |
| |
| /* Debugging info at top of bb. */ |
| |
| static void |
| df_mir_top_dump (basic_block bb, FILE *file) |
| { |
| struct df_mir_bb_info *bb_info = df_mir_get_bb_info (bb->index); |
| |
| if (!bb_info) |
| return; |
| |
| fprintf (file, ";; mir in \t"); |
| df_print_regset (file, &bb_info->in); |
| fprintf (file, ";; mir kill\t"); |
| df_print_regset (file, &bb_info->kill); |
| fprintf (file, ";; mir gen \t"); |
| df_print_regset (file, &bb_info->gen); |
| } |
| |
| /* Debugging info at bottom of bb. */ |
| |
| static void |
| df_mir_bottom_dump (basic_block bb, FILE *file) |
| { |
| struct df_mir_bb_info *bb_info = df_mir_get_bb_info (bb->index); |
| |
| if (!bb_info) |
| return; |
| |
| fprintf (file, ";; mir out \t"); |
| df_print_regset (file, &bb_info->out); |
| } |
| |
| |
| /* Build the datastructure to verify that the solution to the dataflow |
| equations is not dirty. */ |
| |
| static void |
| df_mir_verify_solution_start (void) |
| { |
| basic_block bb; |
| struct df_mir_problem_data *problem_data; |
| if (df_mir->solutions_dirty) |
| return; |
| |
| /* Set it true so that the solution is recomputed. */ |
| df_mir->solutions_dirty = true; |
| |
| problem_data = (struct df_mir_problem_data *) df_mir->problem_data; |
| problem_data->in = XNEWVEC (bitmap_head, last_basic_block_for_fn (cfun)); |
| problem_data->out = XNEWVEC (bitmap_head, last_basic_block_for_fn (cfun)); |
| bitmap_obstack_initialize (&problem_data->mir_bitmaps); |
| |
| FOR_ALL_BB_FN (bb, cfun) |
| { |
| bitmap_initialize (&problem_data->in[bb->index], &problem_data->mir_bitmaps); |
| bitmap_initialize (&problem_data->out[bb->index], &problem_data->mir_bitmaps); |
| bitmap_copy (&problem_data->in[bb->index], DF_MIR_IN (bb)); |
| bitmap_copy (&problem_data->out[bb->index], DF_MIR_OUT (bb)); |
| } |
| } |
| |
| |
| /* Compare the saved datastructure and the new solution to the dataflow |
| equations. */ |
| |
| static void |
| df_mir_verify_solution_end (void) |
| { |
| struct df_mir_problem_data *problem_data; |
| basic_block bb; |
| |
| problem_data = (struct df_mir_problem_data *) df_mir->problem_data; |
| if (!problem_data->out) |
| return; |
| |
| FOR_ALL_BB_FN (bb, cfun) |
| { |
| if ((!bitmap_equal_p (&problem_data->in[bb->index], DF_MIR_IN (bb))) |
| || (!bitmap_equal_p (&problem_data->out[bb->index], DF_MIR_OUT (bb)))) |
| gcc_unreachable (); |
| } |
| |
| /* Cannot delete them immediately because you may want to dump them |
| if the comparison fails. */ |
| FOR_ALL_BB_FN (bb, cfun) |
| { |
| bitmap_clear (&problem_data->in[bb->index]); |
| bitmap_clear (&problem_data->out[bb->index]); |
| } |
| |
| free (problem_data->in); |
| free (problem_data->out); |
| bitmap_obstack_release (&problem_data->mir_bitmaps); |
| free (problem_data); |
| df_mir->problem_data = NULL; |
| } |
| |
| |
| /* All of the information associated with every instance of the problem. */ |
| |
| static const struct df_problem problem_MIR = |
| { |
| DF_MIR, /* Problem id. */ |
| DF_FORWARD, /* Direction. */ |
| df_mir_alloc, /* Allocate the problem specific data. */ |
| df_mir_reset, /* Reset global information. */ |
| df_mir_free_bb_info, /* Free basic block info. */ |
| df_mir_local_compute, /* Local compute function. */ |
| df_mir_init, /* Init the solution specific data. */ |
| df_worklist_dataflow, /* Worklist solver. */ |
| df_mir_confluence_0, /* Confluence operator 0. */ |
| df_mir_confluence_n, /* Confluence operator n. */ |
| df_mir_transfer_function, /* Transfer function. */ |
| NULL, /* Finalize function. */ |
| df_mir_free, /* Free all of the problem information. */ |
| df_mir_free, /* Remove this problem from the stack of dataflow problems. */ |
| NULL, /* Debugging. */ |
| df_mir_top_dump, /* Debugging start block. */ |
| df_mir_bottom_dump, /* Debugging end block. */ |
| NULL, /* Debugging start insn. */ |
| NULL, /* Debugging end insn. */ |
| df_mir_verify_solution_start, /* Incremental solution verify start. */ |
| df_mir_verify_solution_end, /* Incremental solution verify end. */ |
| NULL, /* Dependent problem. */ |
| sizeof (struct df_mir_bb_info),/* Size of entry of block_info array. */ |
| TV_DF_MIR, /* Timing variable. */ |
| false /* Reset blocks on dropping out of blocks_to_analyze. */ |
| }; |
| |
| |
| /* Create a new DATAFLOW instance and add it to an existing instance |
| of DF. */ |
| |
| void |
| df_mir_add_problem (void) |
| { |
| df_add_problem (&problem_MIR); |
| /* These will be initialized when df_scan_blocks processes each |
| block. */ |
| df_mir->out_of_date_transfer_functions = BITMAP_ALLOC (&df_bitmap_obstack); |
| } |
| |
| |
| /* Apply the effects of the gen/kills in INSN to the corresponding bitmaps. */ |
| |
| void |
| df_mir_simulate_one_insn (basic_block bb ATTRIBUTE_UNUSED, rtx_insn *insn, |
| bitmap kill, bitmap gen) |
| { |
| df_ref def; |
| |
| FOR_EACH_INSN_DEF (def, insn) |
| { |
| unsigned int regno = DF_REF_REGNO (def); |
| |
| /* The order of GENs/KILLs matters, so if this def clobbers a reg, any |
| previous gen is irrelevant (and reciprocally). Also, claim that a |
| register is GEN only if it is in all cases. */ |
| if (DF_REF_FLAGS_IS_SET (def, DF_REF_MUST_CLOBBER | DF_REF_MAY_CLOBBER)) |
| { |
| bitmap_set_bit (kill, regno); |
| bitmap_clear_bit (gen, regno); |
| } |
| /* In the worst case, partial and conditional defs can leave bits |
| uninitialized, so assume they do not change anything. */ |
| else if (!DF_REF_FLAGS_IS_SET (def, DF_REF_PARTIAL | DF_REF_CONDITIONAL)) |
| { |
| bitmap_set_bit (gen, regno); |
| bitmap_clear_bit (kill, regno); |
| } |
| } |
| } |
| |
| /*---------------------------------------------------------------------------- |
| CREATE DEF_USE (DU) and / or USE_DEF (UD) CHAINS |
| |
| Link either the defs to the uses and / or the uses to the defs. |
| |
| These problems are set up like the other dataflow problems so that |
| they nicely fit into the framework. They are much simpler and only |
| involve a single traversal of instructions and an examination of |
| the reaching defs information (the dependent problem). |
| ----------------------------------------------------------------------------*/ |
| |
| #define df_chain_problem_p(FLAG) (((enum df_chain_flags)df_chain->local_flags)&(FLAG)) |
| |
| /* Create a du or ud chain from SRC to DST and link it into SRC. */ |
| |
| struct df_link * |
| df_chain_create (df_ref src, df_ref dst) |
| { |
| struct df_link *head = DF_REF_CHAIN (src); |
| struct df_link *link = df_chain->block_pool->allocate (); |
| |
| DF_REF_CHAIN (src) = link; |
| link->next = head; |
| link->ref = dst; |
| return link; |
| } |
| |
| |
| /* Delete any du or ud chains that start at REF and point to |
| TARGET. */ |
| static void |
| df_chain_unlink_1 (df_ref ref, df_ref target) |
| { |
| struct df_link *chain = DF_REF_CHAIN (ref); |
| struct df_link *prev = NULL; |
| |
| while (chain) |
| { |
| if (chain->ref == target) |
| { |
| if (prev) |
| prev->next = chain->next; |
| else |
| DF_REF_CHAIN (ref) = chain->next; |
| df_chain->block_pool->remove (chain); |
| return; |
| } |
| prev = chain; |
| chain = chain->next; |
| } |
| } |
| |
| |
| /* Delete a du or ud chain that leave or point to REF. */ |
| |
| void |
| df_chain_unlink (df_ref ref) |
| { |
| struct df_link *chain = DF_REF_CHAIN (ref); |
| while (chain) |
| { |
| struct df_link *next = chain->next; |
| /* Delete the other side if it exists. */ |
| df_chain_unlink_1 (chain->ref, ref); |
| df_chain->block_pool->remove (chain); |
| chain = next; |
| } |
| DF_REF_CHAIN (ref) = NULL; |
| } |
| |
| |
| /* Copy the du or ud chain starting at FROM_REF and attach it to |
| TO_REF. */ |
| |
| void |
| df_chain_copy (df_ref to_ref, |
| struct df_link *from_ref) |
| { |
| while (from_ref) |
| { |
| df_chain_create (to_ref, from_ref->ref); |
| from_ref = from_ref->next; |
| } |
| } |
| |
| |
| /* Remove this problem from the stack of dataflow problems. */ |
| |
| static void |
| df_chain_remove_problem (void) |
| { |
| bitmap_iterator bi; |
| unsigned int bb_index; |
| |
| /* Wholesale destruction of the old chains. */ |
| if (df_chain->block_pool) |
| delete df_chain->block_pool; |
| |
| EXECUTE_IF_SET_IN_BITMAP (df_chain->out_of_date_transfer_functions, 0, bb_index, bi) |
| { |
| rtx_insn *insn; |
| df_ref def, use; |
| basic_block bb = BASIC_BLOCK_FOR_FN (cfun, bb_index); |
| |
| if (df_chain_problem_p (DF_DU_CHAIN)) |
| FOR_EACH_ARTIFICIAL_DEF (def, bb_index) |
| DF_REF_CHAIN (def) = NULL; |
| if (df_chain_problem_p (DF_UD_CHAIN)) |
| FOR_EACH_ARTIFICIAL_USE (use, bb_index) |
| DF_REF_CHAIN (use) = NULL; |
| |
| FOR_BB_INSNS (bb, insn) |
| if (INSN_P (insn)) |
| { |
| df_insn_info *insn_info = DF_INSN_INFO_GET (insn); |
| if (df_chain_problem_p (DF_DU_CHAIN)) |
| FOR_EACH_INSN_INFO_DEF (def, insn_info) |
| DF_REF_CHAIN (def) = NULL; |
| if (df_chain_problem_p (DF_UD_CHAIN)) |
| { |
| FOR_EACH_INSN_INFO_USE (use, insn_info) |
| DF_REF_CHAIN (use) = NULL; |
| FOR_EACH_INSN_INFO_EQ_USE (use, insn_info) |
| DF_REF_CHAIN (use) = NULL; |
| } |
| } |
| } |
| |
| bitmap_clear (df_chain->out_of_date_transfer_functions); |
| df_chain->block_pool = NULL; |
| } |
| |
| |
| /* Remove the chain problem completely. */ |
| |
| static void |
| df_chain_fully_remove_problem (void) |
| { |
| df_chain_remove_problem (); |
| BITMAP_FREE (df_chain->out_of_date_transfer_functions); |
| free (df_chain); |
| } |
| |
| |
| /* Create def-use or use-def chains. */ |
| |
| static void |
| df_chain_alloc (bitmap all_blocks ATTRIBUTE_UNUSED) |
| { |
| df_chain_remove_problem (); |
| df_chain->block_pool = new object_allocator<df_link> ("df_chain_block pool"); |
| df_chain->optional_p = true; |
| } |
| |
| |
| /* Reset all of the chains when the set of basic blocks changes. */ |
| |
| static void |
| df_chain_reset (bitmap blocks_to_clear ATTRIBUTE_UNUSED) |
| { |
| df_chain_remove_problem (); |
| } |
| |
| |
| /* Create the chains for a list of USEs. */ |
| |
| static void |
| df_chain_create_bb_process_use (bitmap local_rd, |
| df_ref use, |
| int top_flag) |
| { |
| bitmap_iterator bi; |
| unsigned int def_index; |
| |
| for (; use; use = DF_REF_NEXT_LOC (use)) |
| { |
| unsigned int uregno = DF_REF_REGNO (use); |
| if ((!(df->changeable_flags & DF_NO_HARD_REGS)) |
| || (uregno >= FIRST_PSEUDO_REGISTER)) |
| { |
| /* Do not want to go through this for an uninitialized var. */ |
| int count = DF_DEFS_COUNT (uregno); |
| if (count) |
| { |
| if (top_flag == (DF_REF_FLAGS (use) & DF_REF_AT_TOP)) |
| { |
| unsigned int first_index = DF_DEFS_BEGIN (uregno); |
| unsigned int last_index = first_index + count - 1; |
| |
| EXECUTE_IF_SET_IN_BITMAP (local_rd, first_index, def_index, bi) |
| { |
| df_ref def; |
| if (def_index > last_index) |
| break; |
| |
| def = DF_DEFS_GET (def_index); |
| if (df_chain_problem_p (DF_DU_CHAIN)) |
| df_chain_create (def, use); |
| if (df_chain_problem_p (DF_UD_CHAIN)) |
| df_chain_create (use, def); |
| } |
| } |
| } |
| } |
| } |
| } |
| |
| |
| /* Create chains from reaching defs bitmaps for basic block BB. */ |
| |
| static void |
| df_chain_create_bb (unsigned int bb_index) |
| { |
| basic_block bb = BASIC_BLOCK_FOR_FN (cfun, bb_index); |
| struct df_rd_bb_info *bb_info = df_rd_get_bb_info (bb_index); |
| rtx_insn *insn; |
| bitmap_head cpy; |
| |
| bitmap_initialize (&cpy, &bitmap_default_obstack); |
| bitmap_copy (&cpy, &bb_info->in); |
| bitmap_set_bit (df_chain->out_of_date_transfer_functions, bb_index); |
| |
| /* Since we are going forwards, process the artificial uses first |
| then the artificial defs second. */ |
| |
| #ifdef EH_USES |
| /* Create the chains for the artificial uses from the EH_USES at the |
| beginning of the block. */ |
| |
| /* Artificials are only hard regs. */ |
| if (!(df->changeable_flags & DF_NO_HARD_REGS)) |
| df_chain_create_bb_process_use (&cpy, |
| df_get_artificial_uses (bb->index), |
| DF_REF_AT_TOP); |
| #endif |
| |
| df_rd_simulate_artificial_defs_at_top (bb, &cpy); |
| |
| /* Process the regular instructions next. */ |
| FOR_BB_INSNS (bb, insn) |
| if (INSN_P (insn)) |
| { |
| unsigned int uid = INSN_UID (insn); |
| |
| /* First scan the uses and link them up with the defs that remain |
| in the cpy vector. */ |
| df_chain_create_bb_process_use (&cpy, DF_INSN_UID_USES (uid), 0); |
| if (df->changeable_flags & DF_EQ_NOTES) |
| df_chain_create_bb_process_use (&cpy, DF_INSN_UID_EQ_USES (uid), 0); |
| |
| /* Since we are going forwards, process the defs second. */ |
| df_rd_simulate_one_insn (bb, insn, &cpy); |
| } |
| |
| /* Create the chains for the artificial uses of the hard registers |
| at the end of the block. */ |
| if (!(df->changeable_flags & DF_NO_HARD_REGS)) |
| df_chain_create_bb_process_use (&cpy, |
| df_get_artificial_uses (bb->index), |
| 0); |
| |
| bitmap_clear (&cpy); |
| } |
| |
| /* Create def-use chains from reaching use bitmaps for basic blocks |
| in BLOCKS. */ |
| |
| static void |
| df_chain_finalize (bitmap all_blocks) |
| { |
| unsigned int bb_index; |
| bitmap_iterator bi; |
| |
| EXECUTE_IF_SET_IN_BITMAP (all_blocks, 0, bb_index, bi) |
| { |
| df_chain_create_bb (bb_index); |
| } |
| } |
| |
| |
| /* Free all storage associated with the problem. */ |
| |
| static void |
| df_chain_free (void) |
| { |
| delete df_chain->block_pool; |
| BITMAP_FREE (df_chain->out_of_date_transfer_functions); |
| free (df_chain); |
| } |
| |
| |
| /* Debugging info. */ |
| |
| static void |
| df_chain_bb_dump (basic_block bb, FILE *file, bool top) |
| { |
| /* Artificials are only hard regs. */ |
| if (df->changeable_flags & DF_NO_HARD_REGS) |
| return; |
| if (df_chain_problem_p (DF_UD_CHAIN)) |
| { |
| df_ref use; |
| |
| fprintf (file, |
| ";; UD chains for artificial uses at %s\n", |
| top ? "top" : "bottom"); |
| FOR_EACH_ARTIFICIAL_USE (use, bb->index) |
| if ((top && (DF_REF_FLAGS (use) & DF_REF_AT_TOP)) |
| || (!top && !(DF_REF_FLAGS (use) & DF_REF_AT_TOP))) |
| { |
| fprintf (file, ";; reg %d ", DF_REF_REGNO (use)); |
| df_chain_dump (DF_REF_CHAIN (use), file); |
| fprintf (file, "\n"); |
| } |
| } |
| if (df_chain_problem_p (DF_DU_CHAIN)) |
| { |
| df_ref def; |
| |
| fprintf (file, |
| ";; DU chains for artificial defs at %s\n", |
| top ? "top" : "bottom"); |
| FOR_EACH_ARTIFICIAL_DEF (def, bb->index) |
| if ((top && (DF_REF_FLAGS (def) & DF_REF_AT_TOP)) |
| || (!top && !(DF_REF_FLAGS (def) & DF_REF_AT_TOP))) |
| { |
| fprintf (file, ";; reg %d ", DF_REF_REGNO (def)); |
| df_chain_dump (DF_REF_CHAIN (def), file); |
| fprintf (file, "\n"); |
| } |
| } |
| } |
| |
| static void |
| df_chain_top_dump (basic_block bb, FILE *file) |
| { |
| df_chain_bb_dump (bb, file, /*top=*/true); |
| } |
| |
| static void |
| df_chain_bottom_dump (basic_block bb, FILE *file) |
| { |
| df_chain_bb_dump (bb, file, /*top=*/false); |
| } |
| |
| static void |
| df_chain_insn_top_dump (const rtx_insn *insn, FILE *file) |
| { |
| if (df_chain_problem_p (DF_UD_CHAIN) && INSN_P (insn)) |
| { |
| struct df_insn_info *insn_info = DF_INSN_INFO_GET (insn); |
| df_ref use; |
| |
| fprintf (file, ";; UD chains for insn luid %d uid %d\n", |
| DF_INSN_INFO_LUID (insn_info), INSN_UID (insn)); |
| FOR_EACH_INSN_INFO_USE (use, insn_info) |
| if (!HARD_REGISTER_NUM_P (DF_REF_REGNO (use)) |
| || !(df->changeable_flags & DF_NO_HARD_REGS)) |
| { |
| fprintf (file, ";; reg %d ", DF_REF_REGNO (use)); |
| if (DF_REF_FLAGS (use) & DF_REF_READ_WRITE) |
| fprintf (file, "read/write "); |
| df_chain_dump (DF_REF_CHAIN (use), file); |
| fprintf (file, "\n"); |
| } |
| FOR_EACH_INSN_INFO_EQ_USE (use, insn_info) |
| if (!HARD_REGISTER_NUM_P (DF_REF_REGNO (use)) |
| || !(df->changeable_flags & DF_NO_HARD_REGS)) |
| { |
| fprintf (file, ";; eq_note reg %d ", DF_REF_REGNO (use)); |
| df_chain_dump (DF_REF_CHAIN (use), file); |
| fprintf (file, "\n"); |
| } |
| } |
| } |
| |
| static void |
| df_chain_insn_bottom_dump (const rtx_insn *insn, FILE *file) |
| { |
| if (df_chain_problem_p (DF_DU_CHAIN) && INSN_P (insn)) |
| { |
| struct df_insn_info *insn_info = DF_INSN_INFO_GET (insn); |
| df_ref def; |
| fprintf (file, ";; DU chains for insn luid %d uid %d\n", |
| DF_INSN_INFO_LUID (insn_info), INSN_UID (insn)); |
| FOR_EACH_INSN_INFO_DEF (def, insn_info) |
| if (!HARD_REGISTER_NUM_P (DF_REF_REGNO (def)) |
| || !(df->changeable_flags & DF_NO_HARD_REGS)) |
| { |
| fprintf (file, ";; reg %d ", DF_REF_REGNO (def)); |
| if (DF_REF_FLAGS (def) & DF_REF_READ_WRITE) |
| fprintf (file, "read/write "); |
| df_chain_dump (DF_REF_CHAIN (def), file); |
| fprintf (file, "\n"); |
| } |
| fprintf (file, "\n"); |
| } |
| } |
| |
| static const struct df_problem problem_CHAIN = |
| { |
| DF_CHAIN, /* Problem id. */ |
| DF_NONE, /* Direction. */ |
| df_chain_alloc, /* Allocate the problem specific data. */ |
| df_chain_reset, /* Reset global information. */ |
| NULL, /* Free basic block info. */ |
| NULL, /* Local compute function. */ |
| NULL, /* Init the solution specific data. */ |
| NULL, /* Iterative solver. */ |
| NULL, /* Confluence operator 0. */ |
| NULL, /* Confluence operator n. */ |
| NULL, /* Transfer function. */ |
| df_chain_finalize, /* Finalize function. */ |
| df_chain_free, /* Free all of the problem information. */ |
| df_chain_fully_remove_problem,/* Remove this problem from the stack of dataflow problems. */ |
| NULL, /* Debugging. */ |
| df_chain_top_dump, /* Debugging start block. */ |
| df_chain_bottom_dump, /* Debugging end block. */ |
| df_chain_insn_top_dump, /* Debugging start insn. */ |
| df_chain_insn_bottom_dump, /* Debugging end insn. */ |
| NULL, /* Incremental solution verify start. */ |
| NULL, /* Incremental solution verify end. */ |
| &problem_RD, /* Dependent problem. */ |
| sizeof (struct df_scan_bb_info),/* Size of entry of block_info array. */ |
| TV_DF_CHAIN, /* Timing variable. */ |
| false /* Reset blocks on dropping out of blocks_to_analyze. */ |
| }; |
| |
| |
| /* Create a new DATAFLOW instance and add it to an existing instance |
| of DF. The returned structure is what is used to get at the |
| solution. */ |
| |
| void |
| df_chain_add_problem (unsigned int chain_flags) |
| { |
| df_add_problem (&problem_CHAIN); |
| df_chain->local_flags = chain_flags; |
| df_chain->out_of_date_transfer_functions = BITMAP_ALLOC (&df_bitmap_obstack); |
| } |
| |
| #undef df_chain_problem_p |
| |
| |
| /*---------------------------------------------------------------------------- |
| WORD LEVEL LIVE REGISTERS |
| |
| Find the locations in the function where any use of a pseudo can |
| reach in the backwards direction. In and out bitvectors are built |
| for each basic block. We only track pseudo registers that have a |
| size of 2 * UNITS_PER_WORD; bitmaps are indexed by 2 * regno and |
| contain two bits corresponding to each of the subwords. |
| |
| ----------------------------------------------------------------------------*/ |
| |
| /* Private data used to verify the solution for this problem. */ |
| struct df_word_lr_problem_data |
| { |
| /* An obstack for the bitmaps we need for this problem. */ |
| bitmap_obstack word_lr_bitmaps; |
| }; |
| |
| |
| /* Free basic block info. */ |
| |
| static void |
| df_word_lr_free_bb_info (basic_block bb ATTRIBUTE_UNUSED, |
| void *vbb_info) |
| { |
| struct df_word_lr_bb_info *bb_info = (struct df_word_lr_bb_info *) vbb_info; |
| if (bb_info) |
| { |
| bitmap_clear (&bb_info->use); |
| bitmap_clear (&bb_info->def); |
| bitmap_clear (&bb_info->in); |
| bitmap_clear (&bb_info->out); |
| } |
| } |
| |
| |
| /* Allocate or reset bitmaps for DF_WORD_LR blocks. The solution bits are |
| not touched unless the block is new. */ |
| |
| static void |
| df_word_lr_alloc (bitmap all_blocks ATTRIBUTE_UNUSED) |
| { |
| unsigned int bb_index; |
| bitmap_iterator bi; |
| basic_block bb; |
| struct df_word_lr_problem_data *problem_data |
| = XNEW (struct df_word_lr_problem_data); |
| |
| df_word_lr->problem_data = problem_data; |
| |
| df_grow_bb_info (df_word_lr); |
| |
| /* Create the mapping from regnos to slots. This does not change |
| unless the problem is destroyed and recreated. In particular, if |
| we end up deleting the only insn that used a subreg, we do not |
| want to redo the mapping because this would invalidate everything |
| else. */ |
| |
| bitmap_obstack_initialize (&problem_data->word_lr_bitmaps); |
| |
| FOR_EACH_BB_FN (bb, cfun) |
| bitmap_set_bit (df_word_lr->out_of_date_transfer_functions, bb->index); |
| |
| bitmap_set_bit (df_word_lr->out_of_date_transfer_functions, ENTRY_BLOCK); |
| bitmap_set_bit (df_word_lr->out_of_date_transfer_functions, EXIT_BLOCK); |
| |
| EXECUTE_IF_SET_IN_BITMAP (df_word_lr->out_of_date_transfer_functions, 0, bb_index, bi) |
| { |
| struct df_word_lr_bb_info *bb_info = df_word_lr_get_bb_info (bb_index); |
| |
| /* When bitmaps are already initialized, just clear them. */ |
| if (bb_info->use.obstack) |
| { |
| bitmap_clear (&bb_info->def); |
| bitmap_clear (&bb_info->use); |
| } |
| else |
| { |
| bitmap_initialize (&bb_info->use, &problem_data->word_lr_bitmaps); |
| bitmap_initialize (&bb_info->def, &problem_data->word_lr_bitmaps); |
| bitmap_initialize (&bb_info->in, &problem_data->word_lr_bitmaps); |
| bitmap_initialize (&bb_info->out, &problem_data->word_lr_bitmaps); |
| } |
| } |
| |
| df_word_lr->optional_p = true; |
| } |
| |
| |
| /* Reset the global solution for recalculation. */ |
| |
| static void |
| df_word_lr_reset (bitmap all_blocks) |
| { |
| unsigned int bb_index; |
| bitmap_iterator bi; |
| |
| EXECUTE_IF_SET_IN_BITMAP (all_blocks, 0, bb_index, bi) |
| { |
| struct df_word_lr_bb_info *bb_info = df_word_lr_get_bb_info (bb_index); |
| gcc_assert (bb_info); |
| bitmap_clear (&bb_info->in); |
| bitmap_clear (&bb_info->out); |
| } |
| } |
| |
| /* Examine REF, and if it is for a reg we're interested in, set or |
| clear the bits corresponding to its subwords from the bitmap |
| according to IS_SET. LIVE is the bitmap we should update. We do |
| not track hard regs or pseudos of any size other than 2 * |
| UNITS_PER_WORD. |
| We return true if we changed the bitmap, or if we encountered a register |
| we're not tracking. */ |
| |
| bool |
| df_word_lr_mark_ref (df_ref ref, bool is_set, regset live) |
| { |
| rtx orig_reg = DF_REF_REG (ref); |
| rtx reg = orig_reg; |
| machine_mode reg_mode; |
| unsigned regno; |
| /* Left at -1 for whole accesses. */ |
| int which_subword = -1; |
| bool changed = false; |
| |
| if (GET_CODE (reg) == SUBREG) |
| reg = SUBREG_REG (orig_reg); |
| regno = REGNO (reg); |
| reg_mode = GET_MODE (reg); |
| if (regno < FIRST_PSEUDO_REGISTER |
| || GET_MODE_SIZE (reg_mode) != 2 * UNITS_PER_WORD) |
| return true; |
| |
| if (GET_CODE (orig_reg) == SUBREG |
| && df_read_modify_subreg_p (orig_reg)) |
| { |
| gcc_assert (DF_REF_FLAGS_IS_SET (ref, DF_REF_PARTIAL)); |
| if (subreg_lowpart_p (orig_reg)) |
| which_subword = 0; |
| else |
| which_subword = 1; |
| } |
| if (is_set) |
| { |
| if (which_subword != 1) |
| changed |= bitmap_set_bit (live, regno * 2); |
| if (which_subword != 0) |
| changed |= bitmap_set_bit (live, regno * 2 + 1); |
| } |
| else |
| { |
| if (which_subword != 1) |
| changed |= bitmap_clear_bit (live, regno * 2); |
| if (which_subword != 0) |
| changed |= bitmap_clear_bit (live, regno * 2 + 1); |
| } |
| return changed; |
| } |
| |
| /* Compute local live register info for basic block BB. */ |
| |
| static void |
| df_word_lr_bb_local_compute (unsigned int bb_index) |
| { |
| basic_block bb = BASIC_BLOCK_FOR_FN (cfun, bb_index); |
| struct df_word_lr_bb_info *bb_info = df_word_lr_get_bb_info (bb_index); |
| rtx_insn *insn; |
| df_ref def, use; |
| |
| /* Ensure that artificial refs don't contain references to pseudos. */ |
| FOR_EACH_ARTIFICIAL_DEF (def, bb_index) |
| gcc_assert (DF_REF_REGNO (def) < FIRST_PSEUDO_REGISTER); |
| |
| FOR_EACH_ARTIFICIAL_USE (use, bb_index) |
| gcc_assert (DF_REF_REGNO (use) < FIRST_PSEUDO_REGISTER); |
| |
| FOR_BB_INSNS_REVERSE (bb, insn) |
| { |
| if (!NONDEBUG_INSN_P (insn)) |
| continue; |
| |
| df_insn_info *insn_info = DF_INSN_INFO_GET (insn); |
| FOR_EACH_INSN_INFO_DEF (def, insn_info) |
| /* If the def is to only part of the reg, it does |
| not kill the other defs that reach here. */ |
| if (!(DF_REF_FLAGS (def) & (DF_REF_CONDITIONAL))) |
| { |
| df_word_lr_mark_ref (def, true, &bb_info->def); |
| df_word_lr_mark_ref (def, false, &bb_info->use); |
| } |
| FOR_EACH_INSN_INFO_USE (use, insn_info) |
| df_word_lr_mark_ref (use, true, &bb_info->use); |
| } |
| } |
| |
| |
| /* Compute local live register info for each basic block within BLOCKS. */ |
| |
| static void |
| df_word_lr_local_compute (bitmap all_blocks ATTRIBUTE_UNUSED) |
| { |
| unsigned int bb_index; |
| bitmap_iterator bi; |
| |
| EXECUTE_IF_SET_IN_BITMAP (df_word_lr->out_of_date_transfer_functions, 0, bb_index, bi) |
| { |
| if (bb_index == EXIT_BLOCK) |
| { |
| unsigned regno; |
| bitmap_iterator bi; |
| EXECUTE_IF_SET_IN_BITMAP (df->exit_block_uses, FIRST_PSEUDO_REGISTER, |
| regno, bi) |
| gcc_unreachable (); |
| } |
| else |
| df_word_lr_bb_local_compute (bb_index); |
| } |
| |
| bitmap_clear (df_word_lr->out_of_date_transfer_functions); |
| } |
| |
| |
| /* Initialize the solution vectors. */ |
| |
| static void |
| df_word_lr_init (bitmap all_blocks) |
| { |
| unsigned int bb_index; |
| bitmap_iterator bi; |
| |
| EXECUTE_IF_SET_IN_BITMAP (all_blocks, 0, bb_index, bi) |
| { |
| struct df_word_lr_bb_info *bb_info = df_word_lr_get_bb_info (bb_index); |
| bitmap_copy (&bb_info->in, &bb_info->use); |
| bitmap_clear (&bb_info->out); |
| } |
| } |
| |
| |
| /* Confluence function that ignores fake edges. */ |
| |
| static bool |
| df_word_lr_confluence_n (edge e) |
| { |
| bitmap op1 = &df_word_lr_get_bb_info (e->src->index)->out; |
| bitmap op2 = &df_word_lr_get_bb_info (e->dest->index)->in; |
| |
| return bitmap_ior_into (op1, op2); |
| } |
| |
| |
| /* Transfer function. */ |
| |
| static bool |
| df_word_lr_transfer_function (int bb_index) |
| { |
| struct df_word_lr_bb_info *bb_info = df_word_lr_get_bb_info (bb_index); |
| bitmap in = &bb_info->in; |
| bitmap out = &bb_info->out; |
| bitmap use = &bb_info->use; |
| bitmap def = &bb_info->def; |
| |
| return bitmap_ior_and_compl (in, use, out, def); |
| } |
| |
| |
| /* Free all storage associated with the problem. */ |
| |
| static void |
| df_word_lr_free (void) |
| { |
| struct df_word_lr_problem_data *problem_data |
| = (struct df_word_lr_problem_data *)df_word_lr->problem_data; |
| |
| if (df_word_lr->block_info) |
| { |
| df_word_lr->block_info_size = 0; |
| free (df_word_lr->block_info); |
| df_word_lr->block_info = NULL; |
| } |
| |
| BITMAP_FREE (df_word_lr->out_of_date_transfer_functions); |
| bitmap_obstack_release (&problem_data->word_lr_bitmaps); |
| free (problem_data); |
| free (df_word_lr); |
| } |
| |
| |
| /* Debugging info at top of bb. */ |
| |
| static void |
| df_word_lr_top_dump (basic_block bb, FILE *file) |
| { |
| struct df_word_lr_bb_info *bb_info = df_word_lr_get_bb_info (bb->index); |
| if (!bb_info) |
| return; |
| |
| fprintf (file, ";; blr in \t"); |
| df_print_word_regset (file, &bb_info->in); |
| fprintf (file, ";; blr use \t"); |
| df_print_word_regset (file, &bb_info->use); |
| fprintf (file, ";; blr def \t"); |
| df_print_word_regset (file, &bb_info->def); |
| } |
| |
| |
| /* Debugging info at bottom of bb. */ |
| |
| static void |
| df_word_lr_bottom_dump (basic_block bb, FILE *file) |
| { |
| struct df_word_lr_bb_info *bb_info = df_word_lr_get_bb_info (bb->index); |
| if (!bb_info) |
| return; |
| |
| fprintf (file, ";; blr out \t"); |
| df_print_word_regset (file, &bb_info->out); |
| } |
| |
| |
| /* All of the information associated with every instance of the problem. */ |
| |
| static const struct df_problem problem_WORD_LR = |
| { |
| DF_WORD_LR, /* Problem id. */ |
| DF_BACKWARD, /* Direction. */ |
| df_word_lr_alloc, /* Allocate the problem specific data. */ |
| df_word_lr_reset, /* Reset global information. */ |
| df_word_lr_free_bb_info, /* Free basic block info. */ |
| df_word_lr_local_compute, /* Local compute function. */ |
| df_word_lr_init, /* Init the solution specific data. */ |
| df_worklist_dataflow, /* Worklist solver. */ |
| NULL, /* Confluence operator 0. */ |
| df_word_lr_confluence_n, /* Confluence operator n. */ |
| df_word_lr_transfer_function, /* Transfer function. */ |
| NULL, /* Finalize function. */ |
| df_word_lr_free, /* Free all of the problem information. */ |
| df_word_lr_free, /* Remove this problem from the stack of dataflow problems. */ |
| NULL, /* Debugging. */ |
| df_word_lr_top_dump, /* Debugging start block. */ |
| df_word_lr_bottom_dump, /* Debugging end block. */ |
| NULL, /* Debugging start insn. */ |
| NULL, /* Debugging end insn. */ |
| NULL, /* Incremental solution verify start. */ |
| NULL, /* Incremental solution verify end. */ |
| NULL, /* Dependent problem. */ |
| sizeof (struct df_word_lr_bb_info),/* Size of entry of block_info array. */ |
| TV_DF_WORD_LR, /* Timing variable. */ |
| false /* Reset blocks on dropping out of blocks_to_analyze. */ |
| }; |
| |
| |
| /* Create a new DATAFLOW instance and add it to an existing instance |
| of DF. The returned structure is what is used to get at the |
| solution. */ |
| |
| void |
| df_word_lr_add_problem (void) |
| { |
| df_add_problem (&problem_WORD_LR); |
| /* These will be initialized when df_scan_blocks processes each |
| block. */ |
| df_word_lr->out_of_date_transfer_functions = BITMAP_ALLOC (&df_bitmap_obstack); |
| } |
| |
| |
| /* Simulate the effects of the defs of INSN on LIVE. Return true if we changed |
| any bits, which is used by the caller to determine whether a set is |
| necessary. We also return true if there are other reasons not to delete |
| an insn. */ |
| |
| bool |
| df_word_lr_simulate_defs (rtx_insn *insn, bitmap live) |
| { |
| bool changed = false; |
| df_ref def; |
| |
| FOR_EACH_INSN_DEF (def, insn) |
| if (DF_REF_FLAGS (def) & DF_REF_CONDITIONAL) |
| changed = true; |
| else |
| changed |= df_word_lr_mark_ref (def, false, live); |
| return changed; |
| } |
| |
| |
| /* Simulate the effects of the uses of INSN on LIVE. */ |
| |
| void |
| df_word_lr_simulate_uses (rtx_insn *insn, bitmap live) |
| { |
| df_ref use; |
| |
| FOR_EACH_INSN_USE (use, insn) |
| df_word_lr_mark_ref (use, true, live); |
| } |
| |
| /*---------------------------------------------------------------------------- |
| This problem computes REG_DEAD and REG_UNUSED notes. |
| ----------------------------------------------------------------------------*/ |
| |
| static void |
| df_note_alloc (bitmap all_blocks ATTRIBUTE_UNUSED) |
| { |
| df_note->optional_p = true; |
| } |
| |
| /* This is only used if REG_DEAD_DEBUGGING is in effect. */ |
| static void |
| df_print_note (const char *prefix, rtx_insn *insn, rtx note) |
| { |
| if (dump_file) |
| { |
| fprintf (dump_file, "%s %d ", prefix, INSN_UID (insn)); |
| print_rtl (dump_file, note); |
| fprintf (dump_file, "\n"); |
| } |
| } |
| |
| |
| /* After reg-stack, the x86 floating point stack regs are difficult to |
| analyze because of all of the pushes, pops and rotations. Thus, we |
| just leave the notes alone. */ |
| |
| #ifdef STACK_REGS |
| static inline bool |
| df_ignore_stack_reg (int regno) |
| { |
| return regstack_completed |
| && IN_RANGE (regno, FIRST_STACK_REG, LAST_STACK_REG); |
| } |
| #else |
| static inline bool |
| df_ignore_stack_reg (int regno ATTRIBUTE_UNUSED) |
| { |
| return false; |
| } |
| #endif |
| |
| |
| /* Remove all of the REG_DEAD or REG_UNUSED notes from INSN. */ |
| |
| static void |
| df_remove_dead_and_unused_notes (rtx_insn *insn) |
| { |
| rtx *pprev = ®_NOTES (insn); |
| rtx link = *pprev; |
| |
| while (link) |
| { |
| switch (REG_NOTE_KIND (link)) |
| { |
| case REG_DEAD: |
| /* After reg-stack, we need to ignore any unused notes |
| for the stack registers. */ |
| if (df_ignore_stack_reg (REGNO (XEXP (link, 0)))) |
| { |
| pprev = &XEXP (link, 1); |
| link = *pprev; |
| } |
| else |
| { |
| rtx next = XEXP (link, 1); |
| if (REG_DEAD_DEBUGGING) |
| df_print_note ("deleting: ", insn, link); |
| free_EXPR_LIST_node (link); |
| *pprev = link = next; |
| } |
| break; |
| |
| case REG_UNUSED: |
| /* After reg-stack, we need to ignore any unused notes |
| for the stack registers. */ |
| if (df_ignore_stack_reg (REGNO (XEXP (link, 0)))) |
| { |
| pprev = &XEXP (link, 1); |
| link = *pprev; |
| } |
| else |
| { |
| rtx next = XEXP (link, 1); |
| if (REG_DEAD_DEBUGGING) |
| df_print_note ("deleting: ", insn, link); |
| free_EXPR_LIST_node (link); |
| *pprev = link = next; |
| } |
| break; |
| |
| default: |
| pprev = &XEXP (link, 1); |
| link = *pprev; |
| break; |
| } |
| } |
| } |
| |
| /* Remove REG_EQUAL/REG_EQUIV notes referring to dead pseudos using LIVE |
| as the bitmap of currently live registers. */ |
| |
| static void |
| df_remove_dead_eq_notes (rtx_insn *insn, bitmap live) |
| { |
| rtx *pprev = ®_NOTES (insn); |
| rtx link = *pprev; |
| |
| while (link) |
| { |
| switch (REG_NOTE_KIND (link)) |
| { |
| case REG_EQUAL: |
| case REG_EQUIV: |
| { |
| /* Remove the notes that refer to dead registers. As we have at most |
| one REG_EQUAL/EQUIV note, all of EQ_USES will refer to this note |
| so we need to purge the complete EQ_USES vector when removing |
| the note using df_notes_rescan. */ |
| df_ref use; |
| bool deleted = false; |
| |
| FOR_EACH_INSN_EQ_USE (use, insn) |
| if (DF_REF_REGNO (use) > FIRST_PSEUDO_REGISTER |
| && DF_REF_LOC (use) |
| && (DF_REF_FLAGS (use) & DF_REF_IN_NOTE) |
| && !bitmap_bit_p (live, DF_REF_REGNO (use)) |
| && loc_mentioned_in_p (DF_REF_LOC (use), XEXP (link, 0))) |
| { |
| deleted = true; |
| break; |
| } |
| if (deleted) |
| { |
| rtx next; |
| if (REG_DEAD_DEBUGGING) |
| df_print_note ("deleting: ", insn, link); |
| next = XEXP (link, 1); |
| free_EXPR_LIST_node (link); |
| *pprev = link = next; |
| df_notes_rescan (insn); |
| } |
| else |
| { |
| pprev = &XEXP (link, 1); |
| link = *pprev; |
| } |
| break; |
| } |
| |
| default: |
| pprev = &XEXP (link, 1); |
| link = *pprev; |
| break; |
| } |
| } |
| } |
| |
| /* Set a NOTE_TYPE note for REG in INSN. */ |
| |
| static inline void |
| df_set_note (enum reg_note note_type, rtx_insn *insn, rtx reg) |
| { |
| gcc_checking_assert (!DEBUG_INSN_P (insn)); |
| add_reg_note (insn, note_type, reg); |
| } |
| |
| /* A subroutine of df_set_unused_notes_for_mw, with a selection of its |
| arguments. Return true if the register value described by MWS's |
| mw_reg is known to be completely unused, and if mw_reg can therefore |
| be used in a REG_UNUSED note. */ |
| |
| static bool |
| df_whole_mw_reg_unused_p (struct df_mw_hardreg *mws, |
| bitmap live, bitmap artificial_uses) |
| { |
| unsigned int r; |
| |
| /* If MWS describes a partial reference, create REG_UNUSED notes for |
| individual hard registers. */ |
| if (mws->flags & DF_REF_PARTIAL) |
| return false; |
| |
| /* Likewise if some part of the register is used. */ |
| for (r = mws->start_regno; r <= mws->end_regno; r++) |
| if (bitmap_bit_p (live, r) |
| || bitmap_bit_p (artificial_uses, r)) |
| return false; |
| |
| gcc_assert (REG_P (mws->mw_reg)); |
| return true; |
| } |
| |
| |
| /* Set the REG_UNUSED notes for the multiword hardreg defs in INSN |
| based on the bits in LIVE. Do not generate notes for registers in |
| artificial uses. DO_NOT_GEN is updated so that REG_DEAD notes are |
| not generated if the reg is both read and written by the |
| instruction. |
| */ |
| |
| static void |
| df_set_unused_notes_for_mw (rtx_insn *insn, struct df_mw_hardreg *mws, |
| bitmap live, bitmap do_not_gen, |
| bitmap artificial_uses, |
| struct dead_debug_local *debug) |
| { |
| unsigned int r; |
| |
| if (REG_DEAD_DEBUGGING && dump_file) |
| fprintf (dump_file, "mw_set_unused looking at mws[%d..%d]\n", |
| mws->start_regno, mws->end_regno); |
| |
| if (df_whole_mw_reg_unused_p (mws, live, artificial_uses)) |
| { |
| unsigned int regno = mws->start_regno; |
| df_set_note (REG_UNUSED, insn, mws->mw_reg); |
| dead_debug_insert_temp (debug, regno, insn, DEBUG_TEMP_AFTER_WITH_REG); |
| |
| if (REG_DEAD_DEBUGGING) |
| df_print_note ("adding 1: ", insn, REG_NOTES (insn)); |
| |
| bitmap_set_bit (do_not_gen, regno); |
| /* Only do this if the value is totally dead. */ |
| } |
| else |
| for (r = mws->start_regno; r <= mws->end_regno; r++) |
| { |
| if (!bitmap_bit_p (live, r) |
| && !bitmap_bit_p (artificial_uses, r)) |
| { |
| df_set_note (REG_UNUSED, insn, regno_reg_rtx[r]); |
| dead_debug_insert_temp (debug, r, insn, DEBUG_TEMP_AFTER_WITH_REG); |
| if (REG_DEAD_DEBUGGING) |
| df_print_note ("adding 2: ", insn, REG_NOTES (insn)); |
| } |
| bitmap_set_bit (do_not_gen, r); |
| } |
| } |
| |
| |